The Securities and Exchange Commission has not necessarily reviewed the information in this filing and has not determined if it is accurate and complete.
The reader should not assume that the information is accurate and complete.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
FORM 13F

FORM 13F INFORMATION TABLE
OMB APPROVAL
OMB Number: 3235-0006
Estimated average burden
hours per response: 23.8
COLUMN 1 COLUMN 2 COLUMN 3 COLUMN 4 COLUMN 5 COLUMN 6 COLUMN 7 COLUMN 8
VALUE SHRS OR SH/ PUT/ INVESTMENT OTHER VOTING AUTHORITY
NAME OF ISSUER TITLE OF CLASS CUSIP (x$1000) PRN AMT PRN CALL DISCRETION MANAGER SOLE SHARED NONE
3M COMPANY COM 88579y101 6,573 48,450 SH   SOLE   24,225 0 24,225
ABBOTT LABORATORIES COM 002824100 33,797 877,624 SH   SOLE   438,812 0 438,812
ABBVIE INC COM 00287y109 1,772 34,466 SH   SOLE   17,233 0 17,233
ACCENTURE PLC CL A COM g1151c101 27,207 341,277 SH   SOLE   170,638 0 170,638
AMGEN INC COM COM 031162100 543 4,400 SH   SOLE   2,200 0 2,200
APPLE COMPUTER,INC COM 037833100 5,917 11,024 SH   SOLE   5,512 0 5,512
AT&T CORP COM 00206r102 1,756 50,084 SH   SOLE   25,042 0 25,042
AUTOMATIC DATA PROCESSING INC COM 053015103 1,787 23,128 SH   SOLE   11,564 0 11,564
AUTOZONE INC COM 053332102 698 1,300 SH   SOLE   650 0 650
AVALON BAY CMNTYS INC COM 053484101 525 4,000 SH   SOLE   2,000 0 2,000
BASF SE NPV COM d06216317 623 5,600 SH   SOLE   2,800 0 2,800
BAYER AG COM d0712d163 542 4,000 SH   SOLE   2,000 0 2,000
BB&T CORP COM 054937107 2,033 50,602 SH   SOLE   25,301 0 25,301
BERKSHIRE HATHAWAY CL. A COM 084670108 1,124 6 SH   SOLE   3 0 3
BERKSHIRE HATHAWAY CL. B COM 084670702 681 5,450 SH   SOLE   2,725 0 2,725
BOEING CO COM 097023105 3,207 25,559 SH   SOLE   12,779 0 12,779
BOSTON PROPERTIES INC COM 101121101 448 3,910 SH   SOLE   1,955 0 1,955
BRANDYWINE RLTY TR SH BEN INT COM 105368203 2,351 162,618 SH   SOLE   81,309 0 81,309
BRISTOL MYERS SQUIBB COM 110122108 5,334 102,674 SH   SOLE   51,337 0 51,337
BROWN FORMAN CORP CL B (BF/B) COM 115637209 673 7,500 SH   SOLE   3,750 0 3,750
BURKE & HERBERT BANK & TRUST COM 121331102 3,584 1,648 SH   SOLE   824 0 824
C V S CAREMARK CORP COM 126650100 57,910 773,572 SH   SOLE   386,786 0 386,786
CELGENE CORP COM 151020104 11,518 82,506 SH   SOLE   41,253 0 41,253
CHECK POINT SOFTWARE COM m22465104 406 6,000 SH   SOLE   3,000 0 3,000
CHEVRON CORPORATION COM 166764100 49,146 413,300 SH   SOLE   206,650 0 206,650
CHUBB CORP COM 171232101 539 6,040 SH   SOLE   3,020 0 3,020
CHURCH & DWIGHT CO INC COM 171340102 410 5,940 SH   SOLE   2,970 0 2,970
CIMAREX ENERGY COMPANY COM 171798101 476 4,000 SH   SOLE   2,000 0 2,000
CISCO SYSTEMS INC COM 17275r102 753 33,604 SH   SOLE   16,802 0 16,802
CITY NATIONAL CORP. COM 178566105 407 5,170 SH   SOLE   2,585 0 2,585
COCA COLA CO COM 191216100 5,233 135,365 SH   SOLE   67,683 0 67,683
COGNIZANT TECH SOLUTIONS CORP. COM 192446102 38,187 754,678 SH   SOLE   377,339 0 377,339
COLGATE PALMOLIVE CO. COM 194162103 44,921 692,472 SH   SOLE   346,236 0 346,236
CONOCO-PHILIPS COM 20825c104 472 6,711 SH   SOLE   3,355 0 3,355
CONSOLIDATED EDISON INC COM 209115104 687 12,800 SH   SOLE   6,400 0 6,400
CONSTELLATION BRANDS INC. A COM 21036p108 1,258 14,800 SH   SOLE   7,400 0 7,400
CORRECTIONS CORP AMER NEW COM 22025y407 492 15,706 SH   SOLE   7,853 0 7,853
DANAHER CORP DEL COM 235851102 35,207 469,427 SH   SOLE   234,714 0 234,714
DEERE & CO. COM 244199105 3,085 33,980 SH   SOLE   16,990 0 16,990
DESWELL INDUSTRIES INC COM 250639101 166 80,000 SH   SOLE   40,000 0 40,000
DOMINION RESOURCES INC COM 25746u109 909 12,809 SH   SOLE   6,404 0 6,404
DONALDSON COMPANY INC COM 257651109 22,575 532,437 SH   SOLE   266,219 0 266,219
DOW CHEMICAL CO COM 260543103 729 15,000 SH   SOLE   7,500 0 7,500
DR PEPPER SNAPPLE GROUP INC CO COM 26138e109 3,058 56,146 SH   SOLE   28,073 0 28,073
DU PONT E I DE NEMOURS COM 263534109 870 12,966 SH   SOLE   6,483 0 6,483
DUKE ENERGY CORP. COM 26441c204 901 12,656 SH   SOLE   6,328 0 6,328
ENERGY TRANSFER PARTNERS LP COM 29273r109 613 11,400 SH   SOLE   5,700 0 5,700
ENTERPRISE PRODUCTS PPTNS LP COM 293792107 985 14,200 SH   SOLE   7,100 0 7,100
EXXON MOBIL CORPORATION COM 30231g102 43,707 447,449 SH   SOLE   223,724 0 223,724
FASTENAL CO. COM 311900104 775 15,728 SH   SOLE   7,864 0 7,864
FEDERAL REALTY INVST TR SH BEN COM 313747206 458 3,988 SH   SOLE   1,994 0 1,994
FEDEX CORPORATION COM 31428x106 37,229 280,845 SH   SOLE   140,422 0 140,422
FIFTH THIRD BANCORP. COM 316773100 2,354 102,560 SH   SOLE   51,280 0 51,280
FIREEYE COM 31816q101 422 6,850 SH   SOLE   3,425 0 3,425
GARTNER GROUP INC COM 366651107 564 8,120 SH   SOLE   4,060 0 4,060
GENERAL ELEC CO COM COM 369604103 1,860 71,860 SH   SOLE   35,930 0 35,930
GENTEX CORP COM 371901109 436 13,840 SH   SOLE   6,920 0 6,920
GOLDMAN SACHS GROUP INC COM 38141g104 32,620 199,082 SH   SOLE   99,541 0 99,541
GOOGLE INC CLASS A COM 38259p508 53,548 48,046 SH   SOLE   24,023 0 24,023
HELMERICH & PAYNE COM 423452101 446 4,150 SH   SOLE   2,075 0 2,075
HOME DEPOT INC COM 437076102 1,181 14,926 SH   SOLE   7,463 0 7,463
HUNTINGTON BANCSHARES INC COM 446150104 395 39,600 SH   SOLE   19,800 0 19,800
ILLUMINA INC COM 452327109 792 5,330 SH   SOLE   2,665 0 2,665
INTEL CORP COM 458140100 3,617 140,118 SH   SOLE   70,059 0 70,059
INTL BUSINESS MACH COM 459200101 6,539 33,972 SH   SOLE   16,986 0 16,986
INTUIT INC. COM 461202103 27,371 352,132 SH   SOLE   176,066 0 176,066
INVACARE CORP COM 461203101 449 23,526 SH   SOLE   11,763 0 11,763
ISHARES MSCI JAPAN INDEX FUND COM 464286848 1,212 106,950 SH   SOLE   53,475 0 53,475
JOHNSON & JOHNSON COM 478160104 60,183 612,677 SH   SOLE   306,339 0 306,339
JPMORGAN CHASE & CO COM 46625h100 30,717 505,968 SH   SOLE   252,984 0 252,984
JPMORGAN CHASE & CO ALERIAN ML COM 46625h365 428 9,200 SH   SOLE   4,600 0 4,600
KIMBERLY CLARK CORP COM 494368103 859 7,790 SH   SOLE   3,895 0 3,895
KINDER MORGAN ENERGY PARTNERS COM 494550106 540 7,308 SH   SOLE   3,654 0 3,654
LILLY ELI & CO COM 532457108 870 14,780 SH   SOLE   7,390 0 7,390
LINN ENERGY LLC COM 536020100 1,223 43,200 SH   SOLE   21,600 0 21,600
LOCKHEED MARTIN CORP COM 539830109 687 4,206 SH   SOLE   2,103 0 2,103
LOWES COMPANIES INC COM 548661107 37,210 760,939 SH   SOLE   380,469 0 380,469
M D U RES GROUP INC COM 552690109 546 15,900 SH   SOLE   7,950 0 7,950
MARKEL CORP COM 570535104 457 766 SH   SOLE   383 0 383
MARRIOTT INTL INC NEW CL. A COM 571903202 860 15,360 SH   SOLE   7,680 0 7,680
MCDONALDS CORP COM 580135101 3,457 35,269 SH   SOLE   17,635 0 17,635
MEDTRONIC INC COM 585055106 55,045 894,464 SH   SOLE   447,232 0 447,232
MERCK & CO INC NEW COM 58933y105 1,756 30,932 SH   SOLE   15,466 0 15,466
MICROSOFT CORP COM 594918104 41,032 1,001,016 SH   SOLE   500,508 0 500,508
MONSANTO CO NEW DEL COM 61166w101 24,993 219,684 SH   SOLE   109,842 0 109,842
NETAPP INC COM 64110d104 31,542 854,803 SH   SOLE   427,401 0 427,401
NEXTERA ENERGY INC. COM 65339f101 518 5,418 SH   SOLE   2,709 0 2,709
NORFOLK SOUTHERN CORP COM 655844108 4,300 44,256 SH   SOLE   22,128 0 22,128
O REILLY AUTOMOTIVE NEW COM 67103h107 27,511 185,396 SH   SOLE   92,698 0 92,698
OCCULOGIX INC COM NEW COM 878193101 483 71,456 SH   SOLE   35,728 0 35,728
ORACLE CORP COM COM 68389x105 1,458 35,636 SH   SOLE   17,818 0 17,818
PATTERSON COMPANIES COM 703395103 35,886 859,330 SH   SOLE   429,665 0 429,665
PEPSICO INCORPORATED COM 713448108 38,986 466,898 SH   SOLE   233,449 0 233,449
PETSMART INC COM COM 716768106 406 5,890 SH   SOLE   2,945 0 2,945
PFIZER INC COM 717081103 5,689 177,128 SH   SOLE   88,564 0 88,564
PHARMACEUTICAL HOLDRS TR COM 57060u217 467 8,000 SH   SOLE   4,000 0 4,000
PNC BANK CORPORATION COM 693475105 43,174 496,254 SH   SOLE   248,127 0 248,127
PROCTER & GAMBLE COM 742718109 44,203 548,421 SH   SOLE   274,210 0 274,210
QUALCOMM INC COM 747525103 36,589 463,976 SH   SOLE   231,988 0 231,988
ROCKWELL COLLINS INC COM 774341101 31,711 398,026 SH   SOLE   199,013 0 199,013
ROSS STORES INC COM 778296103 499 6,972 SH   SOLE   3,486 0 3,486
ROYAL DUTCH SHELL PLC ADR - A COM 780259206 490 6,700 SH   SOLE   3,350 0 3,350
SCHLUMBERGER LTD COM 806857108 52,608 539,566 SH   SOLE   269,783 0 269,783
SEASPAN CORP SHS ISIN COM y75638109 696 31,522 SH   SOLE   15,761 0 15,761
SIEMENS AG REG SHS ORD COM d69671218 404 3,000 SH   SOLE   1,500 0 1,500
SPDR TRUST SERIES I COM 78462f103 14,682 78,511 SH   SOLE   39,255 0 39,255
STERICYCLE INC COM 858912108 1,117 9,832 SH   SOLE   4,916 0 4,916
STREETTRACKS GOLD TRUST COM 78463v107 999 8,084 SH   SOLE   4,042 0 4,042
STRYKER CORP COM 863667101 35,963 441,430 SH   SOLE   220,715 0 220,715
SYSCO CORP COM COM 871829107 4,388 121,440 SH   SOLE   60,720 0 60,720
TCW STRATEGIC INCOME FUND INC COM 872340104 113 20,680 SH   SOLE   10,340 0 10,340
TEVA PHARMACEUTICAL INDUSTRIES COM 881624209 592 11,200 SH   SOLE   5,600 0 5,600
TEXAS INSTRUMENTS, INC COM 882508104 707 15,000 SH   SOLE   7,500 0 7,500
TJX COMPANIES INC COM 872540109 745 12,282 SH   SOLE   6,141 0 6,141
U.S. BANCORP. COM 902973304 3,552 82,864 SH   SOLE   41,432 0 41,432
UNITED AIRLINES COM 910047109 576 12,900 SH   SOLE   6,450 0 6,450
UNITED NATURAL FOODS, INC. COM 911163103 27,426 386,716 SH   SOLE   193,358 0 193,358
UNITED PARCEL SVC INC B COM 911312106 3,972 40,790 SH   SOLE   20,395 0 20,395
UNITED TECHNOLOGIES CORP COM 913017109 44,897 384,262 SH   SOLE   192,131 0 192,131
VALMONT INDS INC. COM 920253101 23,978 161,096 SH   SOLE   80,548 0 80,548
VANGUARD INTERM TERM BOND ETF COM 921937819 500 6,000 SH   SOLE   3,000 0 3,000
VANGUARD MSCI EUROPE ETF COM 922042874 755 12,800 SH   SOLE   6,400 0 6,400
VERIZON COMMUNICATIONS COM 92343v104 4,667 98,117 SH   SOLE   49,059 0 49,059
WAL-MART STORES INC COM 931142103 34,502 451,423 SH   SOLE   225,712 0 225,712
WALGREEN CO COM COM 931422109 1,327 20,100 SH   SOLE   10,050 0 10,050
WASHINGTON REAL ESTATE COM 939653101 2,739 114,690 SH   SOLE   57,345 0 57,345
WATERS CORP COM COM 941848103 739 6,818 SH   SOLE   3,409 0 3,409
WELLS FARGO & CO COM 949746101 908 18,250 SH   SOLE   9,125 0 9,125
WEYERHAEUSER CO. COM 962166104 3,195 108,850 SH   SOLE   54,425 0 54,425
WILLIS GROUP HOLDINGS LTD COM g96666105 459 10,390 SH   SOLE   5,195 0 5,195
YUM BRANDS INC COM 988498101 28,438 377,212 SH   SOLE   188,606 0 188,606