<?xml version="1.0"?>
<informationTable xmlns="http://www.sec.gov/edgar/document/thirteenf/informationtable" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"><infoTable><nameOfIssuer>3M CO</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>88579Y101</cusip><value>459</value><shrsOrPrnAmt><sshPrnamt>4194</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>3894</Sole><Shared>0</Shared><None>300</None></votingAuthority></infoTable><infoTable><nameOfIssuer>AAON INC</nameOfIssuer><titleOfClass>COM PAR $0.004</titleOfClass><cusip>000360206</cusip><value>16595</value><shrsOrPrnAmt><sshPrnamt>501650</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>443425</Sole><Shared>0</Shared><None>58225</None></votingAuthority></infoTable><infoTable><nameOfIssuer>ABAXIS INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>002567105</cusip><value>24010</value><shrsOrPrnAmt><sshPrnamt>505363</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>443366</Sole><Shared>0</Shared><None>61997</None></votingAuthority></infoTable><infoTable><nameOfIssuer>ABBOTT LABS</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>002824100</cusip><value>403</value><shrsOrPrnAmt><sshPrnamt>11550</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>11550</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>ABBVIE INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>00287Y109</cusip><value>477</value><shrsOrPrnAmt><sshPrnamt>11550</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>11550</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>ACACIA RESH CORP</nameOfIssuer><titleOfClass>ACACIA TCH COM</titleOfClass><cusip>003881307</cusip><value>13508</value><shrsOrPrnAmt><sshPrnamt>604383</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>532983</Sole><Shared>0</Shared><None>71400</None></votingAuthority></infoTable><infoTable><nameOfIssuer>ACCELRYS INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>00430U103</cusip><value>14741</value><shrsOrPrnAmt><sshPrnamt>1754920</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>1560820</Sole><Shared>0</Shared><None>194100</None></votingAuthority></infoTable><infoTable><nameOfIssuer>ACI WORLDWIDE INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>004498101</cusip><value>27770</value><shrsOrPrnAmt><sshPrnamt>597454</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>520904</Sole><Shared>0</Shared><None>76550</None></votingAuthority></infoTable><infoTable><nameOfIssuer>ADOBE SYS INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>00724F101</cusip><value>246</value><shrsOrPrnAmt><sshPrnamt>5400</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>3900</Sole><Shared>0</Shared><None>1500</None></votingAuthority></infoTable><infoTable><nameOfIssuer>ADVENT SOFTWARE INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>007974108</cusip><value>24834</value><shrsOrPrnAmt><sshPrnamt>708338</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>617138</Sole><Shared>0</Shared><None>91200</None></votingAuthority></infoTable><infoTable><nameOfIssuer>ADVISORY BRD CO</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>00762W107</cusip><value>23677</value><shrsOrPrnAmt><sshPrnamt>433249</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>377279</Sole><Shared>0</Shared><None>55970</None></votingAuthority></infoTable><infoTable><nameOfIssuer>AEROVIRONMENT INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>008073108</cusip><value>7952</value><shrsOrPrnAmt><sshPrnamt>394070</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>351345</Sole><Shared>0</Shared><None>42725</None></votingAuthority></infoTable><infoTable><nameOfIssuer>ALIGN TECHNOLOGY INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>016255101</cusip><value>25318</value><shrsOrPrnAmt><sshPrnamt>683523</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>598223</Sole><Shared>0</Shared><None>85300</None></votingAuthority></infoTable><infoTable><nameOfIssuer>ALPS ETF TR</nameOfIssuer><titleOfClass>ALERIAN MLP</titleOfClass><cusip>00162Q866</cusip><value>241</value><shrsOrPrnAmt><sshPrnamt>13500</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>13500</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>ANSYS INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>03662Q105</cusip><value>469</value><shrsOrPrnAmt><sshPrnamt>6411</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>6411</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>ARCHER DANIELS MIDLAND CO</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>039483102</cusip><value>223</value><shrsOrPrnAmt><sshPrnamt>6586</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>6586</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>AUTOMATIC DATA PROCESSING IN</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>053015103</cusip><value>220</value><shrsOrPrnAmt><sshPrnamt>3195</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>2245</Sole><Shared>0</Shared><None>950</None></votingAuthority></infoTable><infoTable><nameOfIssuer>BALCHEM CORP</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>057665200</cusip><value>23747</value><shrsOrPrnAmt><sshPrnamt>530651</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>464676</Sole><Shared>0</Shared><None>65975</None></votingAuthority></infoTable><infoTable><nameOfIssuer>BARD C R INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>067383109</cusip><value>370</value><shrsOrPrnAmt><sshPrnamt>3405</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>2755</Sole><Shared>0</Shared><None>650</None></votingAuthority></infoTable><infoTable><nameOfIssuer>BLACKBAUD INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>09227Q100</cusip><value>21414</value><shrsOrPrnAmt><sshPrnamt>657490</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>572190</Sole><Shared>0</Shared><None>85300</None></votingAuthority></infoTable><infoTable><nameOfIssuer>BOTTOMLINE TECH DEL INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>101388106</cusip><value>26505</value><shrsOrPrnAmt><sshPrnamt>1048025</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>923600</Sole><Shared>0</Shared><None>124425</None></votingAuthority></infoTable><infoTable><nameOfIssuer>C H ROBINSON WORLDWIDE INC</nameOfIssuer><titleOfClass>COM NEW</titleOfClass><cusip>12541W209</cusip><value>353</value><shrsOrPrnAmt><sshPrnamt>6275</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>5255</Sole><Shared>0</Shared><None>1020</None></votingAuthority></infoTable><infoTable><nameOfIssuer>CARBO CERAMICS INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>140781105</cusip><value>12213</value><shrsOrPrnAmt><sshPrnamt>181126</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>159601</Sole><Shared>0</Shared><None>21525</None></votingAuthority></infoTable><infoTable><nameOfIssuer>CHEVRON CORP NEW</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>166764100</cusip><value>692</value><shrsOrPrnAmt><sshPrnamt>5850</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>5850</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>CONTANGO OIL &amp; GAS COMPANY</nameOfIssuer><titleOfClass>COM NEW</titleOfClass><cusip>21075N204</cusip><value>12006</value><shrsOrPrnAmt><sshPrnamt>355740</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>317240</Sole><Shared>0</Shared><None>38500</None></votingAuthority></infoTable><infoTable><nameOfIssuer>COPART INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>217204106</cusip><value>262</value><shrsOrPrnAmt><sshPrnamt>8500</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>8500</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>CORE LABORATORIES N V</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>N22717107</cusip><value>10214</value><shrsOrPrnAmt><sshPrnamt>67349</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>59499</Sole><Shared>0</Shared><None>7850</None></votingAuthority></infoTable><infoTable><nameOfIssuer>COSTAR GROUP INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>22160N109</cusip><value>44863</value><shrsOrPrnAmt><sshPrnamt>347590</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>303335</Sole><Shared>0</Shared><None>44255</None></votingAuthority></infoTable><infoTable><nameOfIssuer>COSTCO WHSL CORP NEW</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>22160K105</cusip><value>395</value><shrsOrPrnAmt><sshPrnamt>3575</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>2760</Sole><Shared>0</Shared><None>815</None></votingAuthority></infoTable><infoTable><nameOfIssuer>CVD EQUIPMENT CORP</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>126601103</cusip><value>171</value><shrsOrPrnAmt><sshPrnamt>20575</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>20575</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>DANAHER CORP DEL</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>235851102</cusip><value>246</value><shrsOrPrnAmt><sshPrnamt>3885</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>2585</Sole><Shared>0</Shared><None>1300</None></votingAuthority></infoTable><infoTable><nameOfIssuer>DOLBY LABORATORIES INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>25659T107</cusip><value>393</value><shrsOrPrnAmt><sshPrnamt>11750</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>11250</Sole><Shared>0</Shared><None>500</None></votingAuthority></infoTable><infoTable><nameOfIssuer>DONALDSON INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>257651109</cusip><value>262</value><shrsOrPrnAmt><sshPrnamt>7360</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>7360</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>DU PONT E I DE NEMOURS &amp; CO</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>263534109</cusip><value>238</value><shrsOrPrnAmt><sshPrnamt>4530</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>4530</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>E M C CORP MASS</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>268648102</cusip><value>273</value><shrsOrPrnAmt><sshPrnamt>11575</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>7975</Sole><Shared>0</Shared><None>3600</None></votingAuthority></infoTable><infoTable><nameOfIssuer>ECOLAB INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>278865100</cusip><value>215</value><shrsOrPrnAmt><sshPrnamt>2525</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>1405</Sole><Shared>0</Shared><None>1120</None></votingAuthority></infoTable><infoTable><nameOfIssuer>ENERGY TRANSFER PRTNRS L P</nameOfIssuer><titleOfClass>UNIT LTD PARTN</titleOfClass><cusip>29273R109</cusip><value>286</value><shrsOrPrnAmt><sshPrnamt>5664</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>5664</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>ENTEROMEDICS INC</nameOfIssuer><titleOfClass>COM NEW</titleOfClass><cusip>29365M208</cusip><value>11</value><shrsOrPrnAmt><sshPrnamt>10000</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>10000</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>EXPRESS SCRIPTS HLDG CO</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>30219G108</cusip><value>223</value><shrsOrPrnAmt><sshPrnamt>3606</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>2756</Sole><Shared>0</Shared><None>850</None></votingAuthority></infoTable><infoTable><nameOfIssuer>EXXON MOBIL CORP</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>30231G102</cusip><value>3979</value><shrsOrPrnAmt><sshPrnamt>44038</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>43638</Sole><Shared>0</Shared><None>400</None></votingAuthority></infoTable><infoTable><nameOfIssuer>FACTSET RESH SYS INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>303075105</cusip><value>13831</value><shrsOrPrnAmt><sshPrnamt>135677</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>121477</Sole><Shared>0</Shared><None>14200</None></votingAuthority></infoTable><infoTable><nameOfIssuer>FARO TECHNOLOGIES INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>311642102</cusip><value>15835</value><shrsOrPrnAmt><sshPrnamt>468217</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>414517</Sole><Shared>0</Shared><None>53700</None></votingAuthority></infoTable><infoTable><nameOfIssuer>FASTENAL CO</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>311900104</cusip><value>439</value><shrsOrPrnAmt><sshPrnamt>9580</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>9580</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>FOREST LABS INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>345838106</cusip><value>265</value><shrsOrPrnAmt><sshPrnamt>6470</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>6070</Sole><Shared>0</Shared><None>400</None></votingAuthority></infoTable><infoTable><nameOfIssuer>FORTINET INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>34959E109</cusip><value>207</value><shrsOrPrnAmt><sshPrnamt>11830</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>11830</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>GARMIN LTD</nameOfIssuer><titleOfClass>SHS</titleOfClass><cusip>H2906T109</cusip><value>322</value><shrsOrPrnAmt><sshPrnamt>8890</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>8390</Sole><Shared>0</Shared><None>500</None></votingAuthority></infoTable><infoTable><nameOfIssuer>GEEKNET INC</nameOfIssuer><titleOfClass>COM NEW</titleOfClass><cusip>36846Q203</cusip><value>141</value><shrsOrPrnAmt><sshPrnamt>10200</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>9700</Sole><Shared>0</Shared><None>500</None></votingAuthority></infoTable><infoTable><nameOfIssuer>GENERAL ELECTRIC CO</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>369604103</cusip><value>318</value><shrsOrPrnAmt><sshPrnamt>13704</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>13704</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>GENTEX CORP</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>371901109</cusip><value>306</value><shrsOrPrnAmt><sshPrnamt>13290</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>13290</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>GEOSPACE TECHNOLOGIES CORP</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>37364X109</cusip><value>18930</value><shrsOrPrnAmt><sshPrnamt>274032</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>240407</Sole><Shared>0</Shared><None>33625</None></votingAuthority></infoTable><infoTable><nameOfIssuer>GRACO INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>384109104</cusip><value>382</value><shrsOrPrnAmt><sshPrnamt>6047</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>6047</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>GRAND CANYON ED INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>38526M106</cusip><value>17070</value><shrsOrPrnAmt><sshPrnamt>529619</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>471469</Sole><Shared>0</Shared><None>58150</None></votingAuthority></infoTable><infoTable><nameOfIssuer>HANSEN MEDICAL INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>411307101</cusip><value>35</value><shrsOrPrnAmt><sshPrnamt>24500</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>24500</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>HEALTHSTREAM INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>42222N103</cusip><value>20980</value><shrsOrPrnAmt><sshPrnamt>828610</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>739710</Sole><Shared>0</Shared><None>88900</None></votingAuthority></infoTable><infoTable><nameOfIssuer>HIBBETT SPORTS INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>428567101</cusip><value>17785</value><shrsOrPrnAmt><sshPrnamt>320039</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>281964</Sole><Shared>0</Shared><None>38075</None></votingAuthority></infoTable><infoTable><nameOfIssuer>HITTITE MICROWAVE CORP</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>43365Y104</cusip><value>19492</value><shrsOrPrnAmt><sshPrnamt>336070</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>296845</Sole><Shared>0</Shared><None>39225</None></votingAuthority></infoTable><infoTable><nameOfIssuer>HOME DEPOT INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>437076102</cusip><value>243</value><shrsOrPrnAmt><sshPrnamt>3135</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>3135</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>IHS INC</nameOfIssuer><titleOfClass>CL A</titleOfClass><cusip>451734107</cusip><value>498</value><shrsOrPrnAmt><sshPrnamt>4770</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>4770</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>INNERWORKINGS INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>45773Y105</cusip><value>10742</value><shrsOrPrnAmt><sshPrnamt>990053</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>867978</Sole><Shared>0</Shared><None>122075</None></votingAuthority></infoTable><infoTable><nameOfIssuer>INTEL CORP</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>458140100</cusip><value>310</value><shrsOrPrnAmt><sshPrnamt>12775</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>10675</Sole><Shared>0</Shared><None>2100</None></votingAuthority></infoTable><infoTable><nameOfIssuer>INTERNATIONAL BUSINESS MACHS</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>459200101</cusip><value>1042</value><shrsOrPrnAmt><sshPrnamt>5450</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>5450</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>INTUIT</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>461202103</cusip><value>378</value><shrsOrPrnAmt><sshPrnamt>6195</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>5295</Sole><Shared>0</Shared><None>900</None></votingAuthority></infoTable><infoTable><nameOfIssuer>INTUITIVE SURGICAL INC</nameOfIssuer><titleOfClass>COM NEW</titleOfClass><cusip>46120E602</cusip><value>220</value><shrsOrPrnAmt><sshPrnamt>435</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>305</Sole><Shared>0</Shared><None>130</None></votingAuthority></infoTable><infoTable><nameOfIssuer>IPG PHOTONICS CORP</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>44980X109</cusip><value>451</value><shrsOrPrnAmt><sshPrnamt>7430</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>7430</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>JOHNSON &amp; JOHNSON</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>478160104</cusip><value>602</value><shrsOrPrnAmt><sshPrnamt>7014</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>6034</Sole><Shared>0</Shared><None>980</None></votingAuthority></infoTable><infoTable><nameOfIssuer>JPMORGAN CHASE &amp; CO</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>46625H100</cusip><value>258</value><shrsOrPrnAmt><sshPrnamt>4891</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>4491</Sole><Shared>0</Shared><None>400</None></votingAuthority></infoTable><infoTable><nameOfIssuer>KIMBERLY CLARK CORP</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>494368103</cusip><value>471</value><shrsOrPrnAmt><sshPrnamt>4850</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>4850</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>MARKEL CORP</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>570535104</cusip><value>574</value><shrsOrPrnAmt><sshPrnamt>1090</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>990</Sole><Shared>0</Shared><None>100</None></votingAuthority></infoTable><infoTable><nameOfIssuer>MASTERCARD INC</nameOfIssuer><titleOfClass>CL A</titleOfClass><cusip>57636Q104</cusip><value>279</value><shrsOrPrnAmt><sshPrnamt>485</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>355</Sole><Shared>0</Shared><None>130</None></votingAuthority></infoTable><infoTable><nameOfIssuer>MEDIDATA SOLUTIONS INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>58471A105</cusip><value>20310</value><shrsOrPrnAmt><sshPrnamt>262240</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>229865</Sole><Shared>0</Shared><None>32375</None></votingAuthority></infoTable><infoTable><nameOfIssuer>MEDIFAST INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>58470H101</cusip><value>8562</value><shrsOrPrnAmt><sshPrnamt>332394</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>298150</Sole><Shared>0</Shared><None>34244</None></votingAuthority></infoTable><infoTable><nameOfIssuer>MERCK &amp; CO INC NEW</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>58933Y105</cusip><value>455</value><shrsOrPrnAmt><sshPrnamt>9800</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>9800</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>MERIDIAN BIOSCIENCE INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>589584101</cusip><value>17464</value><shrsOrPrnAmt><sshPrnamt>812302</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>706777</Sole><Shared>0</Shared><None>105525</None></votingAuthority></infoTable><infoTable><nameOfIssuer>MESA LABS INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>59064R109</cusip><value>3791</value><shrsOrPrnAmt><sshPrnamt>70040</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>65463</Sole><Shared>0</Shared><None>4577</None></votingAuthority></infoTable><infoTable><nameOfIssuer>MICROS SYS INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>594901100</cusip><value>404</value><shrsOrPrnAmt><sshPrnamt>9365</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>9365</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>MICROSOFT CORP</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>594918104</cusip><value>290</value><shrsOrPrnAmt><sshPrnamt>8387</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>6717</Sole><Shared>0</Shared><None>1670</None></votingAuthority></infoTable><infoTable><nameOfIssuer>MIDWAY GOLD CORP</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>598153104</cusip><value>25</value><shrsOrPrnAmt><sshPrnamt>26600</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>26600</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>MORNINGSTAR INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>617700109</cusip><value>16481</value><shrsOrPrnAmt><sshPrnamt>212438</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>184463</Sole><Shared>0</Shared><None>27975</None></votingAuthority></infoTable><infoTable><nameOfIssuer>MYRIAD GENETICS INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>62855J104</cusip><value>476</value><shrsOrPrnAmt><sshPrnamt>17730</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>17230</Sole><Shared>0</Shared><None>500</None></votingAuthority></infoTable><infoTable><nameOfIssuer>NATIONAL RESH CORP</nameOfIssuer><titleOfClass>CL A</titleOfClass><cusip>637372202</cusip><value>16381</value><shrsOrPrnAmt><sshPrnamt>910042</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>794791</Sole><Shared>0</Shared><None>115251</None></votingAuthority></infoTable><infoTable><nameOfIssuer>NATIONAL RESH CORP</nameOfIssuer><titleOfClass>CL B</titleOfClass><cusip>637372301</cusip><value>5299</value><shrsOrPrnAmt><sshPrnamt>151647</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>132439</Sole><Shared>0</Shared><None>19208</None></votingAuthority></infoTable><infoTable><nameOfIssuer>NEOGEN CORP</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>640491106</cusip><value>25408</value><shrsOrPrnAmt><sshPrnamt>457307</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>399083</Sole><Shared>0</Shared><None>58224</None></votingAuthority></infoTable><infoTable><nameOfIssuer>NIC INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>62914B100</cusip><value>15503</value><shrsOrPrnAmt><sshPrnamt>937851</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>820301</Sole><Shared>0</Shared><None>117550</None></votingAuthority></infoTable><infoTable><nameOfIssuer>NIKE INC</nameOfIssuer><titleOfClass>CL B</titleOfClass><cusip>654106103</cusip><value>267</value><shrsOrPrnAmt><sshPrnamt>4185</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>3385</Sole><Shared>0</Shared><None>800</None></votingAuthority></infoTable><infoTable><nameOfIssuer>NVE CORP</nameOfIssuer><titleOfClass>COM NEW</titleOfClass><cusip>629445206</cusip><value>8339</value><shrsOrPrnAmt><sshPrnamt>178107</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>156113</Sole><Shared>0</Shared><None>21994</None></votingAuthority></infoTable><infoTable><nameOfIssuer>OMNICELL INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>68213N109</cusip><value>8580</value><shrsOrPrnAmt><sshPrnamt>417531</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>389264</Sole><Shared>0</Shared><None>28267</None></votingAuthority></infoTable><infoTable><nameOfIssuer>PEPSICO INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>713448108</cusip><value>258</value><shrsOrPrnAmt><sshPrnamt>3150</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>2750</Sole><Shared>0</Shared><None>400</None></votingAuthority></infoTable><infoTable><nameOfIssuer>PFIZER INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>717081103</cusip><value>599</value><shrsOrPrnAmt><sshPrnamt>21385</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>21385</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>POLARIS INDS INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>731068102</cusip><value>560</value><shrsOrPrnAmt><sshPrnamt>5890</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>5890</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>PPL CORP</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>69351T106</cusip><value>262</value><shrsOrPrnAmt><sshPrnamt>8658</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>8658</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>PRECISION CASTPARTS CORP</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>740189105</cusip><value>237</value><shrsOrPrnAmt><sshPrnamt>1050</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>770</Sole><Shared>0</Shared><None>280</None></votingAuthority></infoTable><infoTable><nameOfIssuer>PROCTER &amp; GAMBLE CO</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>742718109</cusip><value>757</value><shrsOrPrnAmt><sshPrnamt>9826</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>8876</Sole><Shared>0</Shared><None>950</None></votingAuthority></infoTable><infoTable><nameOfIssuer>PROS HOLDINGS INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>74346Y103</cusip><value>29488</value><shrsOrPrnAmt><sshPrnamt>984570</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>866870</Sole><Shared>0</Shared><None>117700</None></votingAuthority></infoTable><infoTable><nameOfIssuer>PROTO LABS INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>743713109</cusip><value>28351</value><shrsOrPrnAmt><sshPrnamt>436367</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>382617</Sole><Shared>0</Shared><None>53750</None></votingAuthority></infoTable><infoTable><nameOfIssuer>QLIK TECHNOLOGIES INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>74733T105</cusip><value>340</value><shrsOrPrnAmt><sshPrnamt>12020</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>12020</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>RAVEN INDS INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>754212108</cusip><value>30070</value><shrsOrPrnAmt><sshPrnamt>1002995</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>875877</Sole><Shared>0</Shared><None>127118</None></votingAuthority></infoTable><infoTable><nameOfIssuer>ROLLINS INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>775711104</cusip><value>20379</value><shrsOrPrnAmt><sshPrnamt>786850</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>685920</Sole><Shared>0</Shared><None>100930</None></votingAuthority></infoTable><infoTable><nameOfIssuer>SCHLUMBERGER LTD</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>806857108</cusip><value>249</value><shrsOrPrnAmt><sshPrnamt>3475</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>2625</Sole><Shared>0</Shared><None>850</None></votingAuthority></infoTable><infoTable><nameOfIssuer>SCIQUEST INC NEW</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>80908T101</cusip><value>20419</value><shrsOrPrnAmt><sshPrnamt>815144</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>707711</Sole><Shared>0</Shared><None>107433</None></votingAuthority></infoTable><infoTable><nameOfIssuer>SIGMA ALDRICH CORP</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>826552101</cusip><value>208</value><shrsOrPrnAmt><sshPrnamt>2590</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>1670</Sole><Shared>0</Shared><None>920</None></votingAuthority></infoTable><infoTable><nameOfIssuer>SIMPSON MANUFACTURING CO INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>829073105</cusip><value>23509</value><shrsOrPrnAmt><sshPrnamt>799072</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>699122</Sole><Shared>0</Shared><None>99950</None></votingAuthority></infoTable><infoTable><nameOfIssuer>SIRONA DENTAL SYSTEMS INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>82966C103</cusip><value>269</value><shrsOrPrnAmt><sshPrnamt>4090</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>4090</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>SM ENERGY CO</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>78454L100</cusip><value>456</value><shrsOrPrnAmt><sshPrnamt>7600</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>7400</Sole><Shared>0</Shared><None>200</None></votingAuthority></infoTable><infoTable><nameOfIssuer>SMUCKER J M CO</nameOfIssuer><titleOfClass>COM NEW</titleOfClass><cusip>832696405</cusip><value>613</value><shrsOrPrnAmt><sshPrnamt>5946</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>5946</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>SOURCEFIRE INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>83616T108</cusip><value>24034</value><shrsOrPrnAmt><sshPrnamt>432659</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>378830</Sole><Shared>0</Shared><None>53829</None></votingAuthority></infoTable><infoTable><nameOfIssuer>SPDR S&amp;P 500 ETF TR</nameOfIssuer><titleOfClass>TR UNIT</titleOfClass><cusip>78462F103</cusip><value>300</value><shrsOrPrnAmt><sshPrnamt>1870</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>1870</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>SPS COMM INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>78463M107</cusip><value>5479</value><shrsOrPrnAmt><sshPrnamt>99613</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>80238</Sole><Shared>0</Shared><None>19375</None></votingAuthority></infoTable><infoTable><nameOfIssuer>STAMPS COM INC</nameOfIssuer><titleOfClass>COM NEW</titleOfClass><cusip>852857200</cusip><value>30892</value><shrsOrPrnAmt><sshPrnamt>784266</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>688141</Sole><Shared>0</Shared><None>96125</None></votingAuthority></infoTable><infoTable><nameOfIssuer>STERICYCLE INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>858912108</cusip><value>277</value><shrsOrPrnAmt><sshPrnamt>2505</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>2105</Sole><Shared>0</Shared><None>400</None></votingAuthority></infoTable><infoTable><nameOfIssuer>STRATASYS LTD</nameOfIssuer><titleOfClass>SHS</titleOfClass><cusip>M85548101</cusip><value>21842</value><shrsOrPrnAmt><sshPrnamt>260833</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>228963</Sole><Shared>0</Shared><None>31870</None></votingAuthority></infoTable><infoTable><nameOfIssuer>STREAMLINE HEALTH SOLUTIONS</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>86323X106</cusip><value>218</value><shrsOrPrnAmt><sshPrnamt>33200</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>33200</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>SUN HYDRAULICS CORP</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>866942105</cusip><value>29917</value><shrsOrPrnAmt><sshPrnamt>956419</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>839345</Sole><Shared>0</Shared><None>117074</None></votingAuthority></infoTable><infoTable><nameOfIssuer>TECHNE CORP</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>878377100</cusip><value>10125</value><shrsOrPrnAmt><sshPrnamt>146573</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>131998</Sole><Shared>0</Shared><None>14575</None></votingAuthority></infoTable><infoTable><nameOfIssuer>TRACTOR SUPPLY CO</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>892356106</cusip><value>453</value><shrsOrPrnAmt><sshPrnamt>3850</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>3850</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>TRIMBLE NAVIGATION LTD</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>896239100</cusip><value>654</value><shrsOrPrnAmt><sshPrnamt>25150</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>25150</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>TYLER TECHNOLOGIES INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>902252105</cusip><value>31551</value><shrsOrPrnAmt><sshPrnamt>460268</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>402943</Sole><Shared>0</Shared><None>57325</None></votingAuthority></infoTable><infoTable><nameOfIssuer>UNDER ARMOUR INC</nameOfIssuer><titleOfClass>CL A</titleOfClass><cusip>904311107</cusip><value>300</value><shrsOrPrnAmt><sshPrnamt>5020</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>5020</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>UNIFI INC</nameOfIssuer><titleOfClass>COM NEW</titleOfClass><cusip>904677200</cusip><value>3137</value><shrsOrPrnAmt><sshPrnamt>151759</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>149759</Sole><Shared>0</Shared><None>2000</None></votingAuthority></infoTable><infoTable><nameOfIssuer>UNION PAC CORP</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>907818108</cusip><value>725</value><shrsOrPrnAmt><sshPrnamt>4700</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>4700</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>UNITED TECHNOLOGIES CORP</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>913017109</cusip><value>277</value><shrsOrPrnAmt><sshPrnamt>2982</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>2982</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>URBAN OUTFITTERS INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>917047102</cusip><value>251</value><shrsOrPrnAmt><sshPrnamt>6230</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>5930</Sole><Shared>0</Shared><None>300</None></votingAuthority></infoTable><infoTable><nameOfIssuer>USA MOBILITY INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>90341G103</cusip><value>208</value><shrsOrPrnAmt><sshPrnamt>15350</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>15350</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>VERISK ANALYTICS INC</nameOfIssuer><titleOfClass>CL A</titleOfClass><cusip>92345Y106</cusip><value>607</value><shrsOrPrnAmt><sshPrnamt>10160</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>9160</Sole><Shared>0</Shared><None>1000</None></votingAuthority></infoTable><infoTable><nameOfIssuer>VERIZON COMMUNICATIONS INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>92343V104</cusip><value>355</value><shrsOrPrnAmt><sshPrnamt>7050</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>7050</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>WELLS FARGO &amp; CO NEW</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>949746101</cusip><value>202</value><shrsOrPrnAmt><sshPrnamt>4900</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>4500</Sole><Shared>0</Shared><None>400</None></votingAuthority></infoTable><infoTable><nameOfIssuer>WESTWOOD HLDGS GROUP INC</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>961765104</cusip><value>18935</value><shrsOrPrnAmt><sshPrnamt>441164</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><otherManager>
		</otherManager><votingAuthority><Sole>388470</Sole><Shared>0</Shared><None>52694</None></votingAuthority></infoTable></informationTable>
