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
AAR Corp COM 000361105 3,422 73,600 SH   SOLE   73,600 0 0
Abbott Laboratories COM 002824100 234,528 3,845,348 SH   SOLE   2,960,455 0 884,893
Abbvie Inc COM 00287Y109 15,841 170,977 SH   SOLE   42,024 0 128,953
Accenture PLC Cl A COM G1151C101 200 1,225 SH   SOLE   0 0 1,225
Actuant Corp COM 00508X203 12,203 415,775 SH   SOLE   415,775 0 0
Adobe Systems COM 00724F101 512 2,100 SH   SOLE   0 0 2,100
ALLETE, Inc. COM 018522300 9,470 122,338 SH   SOLE   74,010 0 48,328
Alliant Energy Corp. COM 018802108 322 7,597 SH   SOLE   0 0 7,597
Alphabet Inc Class A COM 02079K305 1,556 1,378 SH   SOLE   617 0 761
Alphabet Inc Class C COM 02079K107 265,148 237,662 SH   SOLE   203,074 0 34,588
Altria Group Inc COM 02209S103 379 6,682 SH   SOLE   413 0 6,269
Amazon Com Inc COM 023135106 1,030 606 SH   SOLE   30 0 576
American Express COM 025816109 130,857 1,335,271 SH   SOLE   1,032,994 0 302,277
American Tower Cl A COM 03027X100 453 3,145 SH   SOLE   0 0 3,145
Ameriprise Financial COM 03076C106 326 2,331 SH   SOLE   90 0 2,241
Amgen COM 031162100 1,886 10,219 SH   SOLE   2,006 0 8,213
Apogee Enterprises, Inc COM 037598109 15,194 315,430 SH   SOLE   313,830 0 1,600
Apple Computer COM 037833100 6,045 32,658 SH   SOLE   8,523 0 24,135
Applied Materials Inc COM 038222105 465 10,077 SH   SOLE   1,750 0 8,327
Assoc Banc Corp COM 045487105 66,527 2,436,895 SH   SOLE   2,023,509 0 413,386
AT&T COM 00206R102 1,419 44,194 SH   SOLE   1,165 0 43,029
Autoliv Inc COM 052800109 274 1,910 SH   SOLE   0 0 1,910
Automatic Data Proc COM 053015103 678 5,052 SH   SOLE   1,850 0 3,202
Badger Meter Inc COM 056525108 73,942 1,654,188 SH   SOLE   1,279,250 0 374,938
Bank of America Corp COM 060505104 359 12,738 SH   SOLE   200 0 12,538
Baxter International COM 071813109 54,826 742,496 SH   SOLE   432,208 0 310,288
Becton Dickinson & Co COM 075887109 953 3,980 SH   SOLE   1,217 0 2,763
Bemis COM 081437105 152,702 3,617,667 SH   SOLE   2,670,467 0 947,200
Berkshire Hathaway COM 084670108 2,820 10 SH   SOLE   0 0 10
Berkshire Hathaway B COM 084670702 4,081 21,867 SH   SOLE   1,600 0 20,267
Bio-Techne Corp COM 09073M104 191,104 1,291,677 SH   SOLE   1,025,596 0 266,081
Biogen Inc. COM 09062X103 297 1,025 SH   SOLE   0 0 1,025
Black Hills Corp COM 092113109 10,198 166,610 SH   SOLE   166,610 0 0
Boeing COM 097023105 1,298 3,869 SH   SOLE   1,595 0 2,274
BP PLC COM 055622104 1,368 29,950 SH   SOLE   6,384 0 23,566
Bristol-Myers Squibb COM 110122108 15,437 278,944 SH   SOLE   168,596 0 110,348
Calyxt Inc COM 13173L107 4,031 215,909 SH   SOLE   215,909 0 0
Cardiovascular Sys Inc COM 141619106 2,625 81,162 SH   SOLE   81,162 0 0
Casey's General Stores COM 147528103 11,454 109,000 SH   SOLE   109,000 0 0
Catalent, Inc. COM 148806102 13,567 323,863 SH   SOLE   323,260 0 603
Caterpillar COM 149123101 1,091 8,040 SH   SOLE   800 0 7,240
Celgene Corp COM 151020104 237 2,980 SH   SOLE   0 0 2,980
Centerpoint Energy Inc COM 15189T107 207 7,459 SH   SOLE   0 0 7,459
Cerner Corp COM 156782104 230 3,855 SH   SOLE   0 0 3,855
CH Robinson Worldwide COM 12541W209 152,630 1,824,408 SH   SOLE   1,392,721 0 431,687
Charles Schwab COM 808513105 40,598 794,487 SH   SOLE   559,060 0 235,427
Chevron Corp COM 166764100 35,410 280,076 SH   SOLE   111,195 0 168,881
Cisco COM 17275R102 1,576 36,634 SH   SOLE   5,616 0 31,018
Clorox COM 189054109 205 1,513 SH   SOLE   1,350 0 163
Coca-Cola COM 191216100 1,390 31,686 SH   SOLE   9,325 0 22,361
Colgate-Palmolive COM 194162103 589 9,094 SH   SOLE   0 0 9,094
Comcast New Cl A COM 20030N101 248 7,552 SH   SOLE   654 0 6,898
ConocoPhillips COM 20825C104 8,302 119,242 SH   SOLE   7,662 0 111,580
CoreSite Realty Corp COM 21870Q105 89,220 805,086 SH   SOLE   711,490 0 93,596
Corning COM 219350105 63,948 2,324,548 SH   SOLE   1,833,512 0 491,036
Costco Wholesale COM 22160K105 767 3,672 SH   SOLE   800 0 2,872
Cray Inc COM 225223304 52,539 2,135,718 SH   SOLE   1,750,056 0 385,662
CSX Corporation COM 126408103 587 9,200 SH   SOLE   0 0 9,200
Cullen Frost Bankers COM 229899109 14,255 131,700 SH   SOLE   129,395 0 2,305
CyberOptics Corp COM 232517102 4,648 267,100 SH   SOLE   267,100 0 0
Deere & Co. COM 244199105 223 1,592 SH   SOLE   112 0 1,480
Deluxe Corp COM 248019101 4,131 62,393 SH   SOLE   0 0 62,393
Disney COM 254687106 208,350 1,987,881 SH   SOLE   1,578,617 0 409,264
Dominion Energy, Inc. COM 25746U109 248 3,632 SH   SOLE   0 0 3,632
Donaldson COM 257651109 243,649 5,400,013 SH   SOLE   4,184,528 0 1,215,485
DowDupont Inc. COM 26078J100 752 11,410 SH   SOLE   1,922 0 9,488
Duke Energy Corp New COM 26441C204 217 2,750 SH   SOLE   0 0 2,750
Ecolab Inc COM 278865100 341,255 2,431,804 SH   SOLE   1,819,987 0 611,817
EMC Insurance Group COM 268664109 5,440 195,828 SH   SOLE   195,828 0 0
Emerson Electric COM 291011104 32,995 477,214 SH   SOLE   140,443 0 336,771
Exelon Corp COM 30161N101 589 13,828 SH   SOLE   0 0 13,828
Exxon Mobil COM 30231G102 55,068 665,635 SH   SOLE   246,885 0 418,750
Facebook Inc Class A COM 30303M102 264 1,358 SH   SOLE   384 0 974
Fastenal Co. COM 311900104 141,689 2,943,875 SH   SOLE   2,266,635 0 677,240
Fedex Corp. COM 31428X106 486 2,140 SH   SOLE   0 0 2,140
Fiserv COM 337738108 150,132 2,026,340 SH   SOLE   1,551,166 0 475,174
Fleetcor Technologies Inc COM 339041105 211 1,000 SH   SOLE   0 0 1,000
Generac Hldgs COM 368736104 40,042 774,055 SH   SOLE   679,696 0 94,359
General Electric COM 369604103 18,068 1,327,529 SH   SOLE   526,608 0 800,921
General Mills COM 370334104 138,316 3,125,088 SH   SOLE   2,246,350 0 878,738
Gentherm Inc COM 37253A103 29,972 762,635 SH   SOLE   701,448 0 61,187
Glacier Bancorp Inc COM 37637Q105 14,255 368,530 SH   SOLE   368,160 0 370
Graco Inc COM 384109104 250,124 5,531,277 SH   SOLE   3,908,351 0 1,622,927
Great Western Bancorp Inc. COM 391416104 91,562 2,180,568 SH   SOLE   1,839,853 0 340,715
Hawkins Chemical COM 420261109 4,352 123,100 SH   SOLE   116,600 0 6,500
HB Fuller COM 359694106 141,029 2,627,217 SH   SOLE   2,148,606 0 478,611
Hershey COM 427866108 11,791 126,703 SH   SOLE   90,845 0 35,858
Home Depot COM 437076102 66,299 339,821 SH   SOLE   194,504 0 145,317
Honeywell Inc COM 438516106 281,604 1,954,904 SH   SOLE   1,432,941 0 521,963
Hormel COM 440452100 257,050 6,908,078 SH   SOLE   5,400,594 0 1,507,484
Hub Group Inc Cl A COM 443320106 9,381 188,380 SH   SOLE   188,380 0 0
IBM COM 459200101 12,713 91,002 SH   SOLE   39,337 0 51,665
IDEXX Laboratories, Inc COM 45168D104 937 4,298 SH   SOLE   0 0 4,298
Illinois Tool Works Inc COM 452308109 478 3,450 SH   SOLE   0 0 3,450
Inspire Medical Systems Inc COM 457730109 4,211 118,100 SH   SOLE   118,100 0 0
Intel COM 458140100 19,952 401,372 SH   SOLE   66,495 0 334,877
Intl Flavors/Fragr COM 459506101 306 2,466 SH   SOLE   2,000 0 466
Intricon Corp Com COM 46121H109 4,409 109,400 SH   SOLE   109,400 0 0
IPG Photonics Corp COM 44980X109 441 2,000 SH   SOLE   0 0 2,000
J.P. Morgan Chase & Co COM 46625H100 25,983 249,358 SH   SOLE   151,081 0 98,277
Johnson & Johnson COM 478160104 267,820 2,207,186 SH   SOLE   1,663,493 0 543,693
Kellogg COM 487836108 297 4,250 SH   SOLE   0 0 4,250
Kimberly-Clark COM 494368103 21,962 208,489 SH   SOLE   88,609 0 119,880
Lilly (Eli) COM 532457108 88,443 1,036,478 SH   SOLE   737,680 0 298,798
Littelfuse Inc. COM 537008104 18,334 80,350 SH   SOLE   80,300 0 50
Lowes Companies Inc COM 548661107 513 5,369 SH   SOLE   0 0 5,369
Marcus Corp. COM 566330106 9,910 304,923 SH   SOLE   304,923 0 0
Marsh & McLennan COM 571748102 202 2,466 SH   SOLE   1,000 0 1,466
MasterCard Inc COM 57636Q104 530 2,695 SH   SOLE   200 0 2,495
McDonald's Corp COM 580135101 2,424 15,471 SH   SOLE   11,000 0 4,471
MDU Resources Group COM 552690109 2,326 81,106 SH   SOLE   1,450 0 79,656
Medtronic COM G5960L103 296,587 3,464,399 SH   SOLE   2,641,872 0 822,527
Merck & Co Inc COM 58933Y105 5,522 90,969 SH   SOLE   11,650 0 79,319
Microsoft COM 594918104 114,122 1,157,311 SH   SOLE   938,176 0 219,135
MMM Co. COM 88579Y101 299,391 1,521,917 SH   SOLE   1,010,971 0 510,946
MTS Systems COM 553777103 1,820 34,575 SH   SOLE   3,300 0 31,275
Neogen Corp COM 640491106 238 2,965 SH   SOLE   0 0 2,965
Nestle S A Reg B ADR COM 641069406 205 2,650 SH   SOLE   1,550 0 1,100
NextEra Energy, Inc. COM 65339F101 398 2,380 SH   SOLE   0 0 2,380
Nike COM 654106103 351 4,400 SH   SOLE   1,200 0 3,200
Norfolk Southern Corp COM 655844108 779 5,165 SH   SOLE   0 0 5,165
Northrop Grumman Corp COM 666807102 244 792 SH   SOLE   500 0 292
Novartis COM 66987V109 242 3,200 SH   SOLE   850 0 2,350
NVE Corp COM 629445206 40,080 329,114 SH   SOLE   284,999 0 44,115
nVent Electric PLC COM G6700G107 56,107 2,235,332 SH   SOLE   1,610,452 0 624,880
NW Biotherapeutics COM 66737P600 3 12,500 SH   SOLE   0 0 12,500
Oasis Petroleum Inc COM 674215108 5,977 460,820 SH   SOLE   460,820 0 0
Old Natl Bancorp Ind COM 680033107 96,373 5,181,339 SH   SOLE   4,626,899 0 554,440
Oracle Sys COM 68389X105 1,414 32,092 SH   SOLE   447 0 31,645
Oshkosh Corp COM 688239201 12,050 171,357 SH   SOLE   171,290 0 67
Patterson Companies COM 703395103 30,621 1,350,716 SH   SOLE   903,594 0 447,122
Paychex COM 704326107 294 4,297 SH   SOLE   0 0 4,297
Pentair PLC COM G7S00T104 91,614 2,177,136 SH   SOLE   1,570,840 0 606,296
PepsiCo Inc COM 713448108 1,394 12,807 SH   SOLE   1,220 0 11,587
Pfizer Inc COM 717081103 144,094 3,971,728 SH   SOLE   2,987,023 0 984,705
Philip Morris Intl Inc COM 718172109 638 7,905 SH   SOLE   393 0 7,512
Phillips 66 COM 718546104 2,441 21,736 SH   SOLE   200 0 21,536
Physicians Realty Tr COM 71943U104 12,836 805,240 SH   SOLE   785,240 0 20,000
Polaris Ind COM 731068102 465 3,803 SH   SOLE   3,050 0 753
Praxair COM 74005P104 324 2,051 SH   SOLE   0 0 2,051
Premier Inc Cl A COM 74051N102 9,970 274,039 SH   SOLE   274,039 0 0
Principal Financial COM 74251V102 135,464 2,558,334 SH   SOLE   2,008,475 0 549,859
Procter & Gamble COM 742718109 27,559 353,046 SH   SOLE   80,249 0 272,797
Proto Labs COM 743713109 36,491 306,773 SH   SOLE   243,911 0 62,862
PureCycle Corp COM 746228303 113 11,855 SH   SOLE   0 0 11,855
QCR Holdings COM 74727A104 4,317 90,975 SH   SOLE   90,975 0 0
Qualcomm, Inc. COM 747525103 75,308 1,341,918 SH   SOLE   1,111,010 0 230,908
Raven Industries Inc COM 754212108 6,247 162,466 SH   SOLE   161,966 0 500
Raytheon Co COM 755111507 266 1,375 SH   SOLE   0 0 1,375
Roche Hldg Ltd ADR COM 771195104 151,447 5,481,244 SH   SOLE   4,545,384 0 935,860
Rockwell Automation COM 773903109 249 1,500 SH   SOLE   500 0 1,000
Royal Dutch Shell Spons ADR A COM 780259206 368 5,320 SH   SOLE   400 0 4,920
Schlumberger COM 806857108 142,433 2,124,910 SH   SOLE   1,653,407 0 471,503
SEI Investments Co COM 784117103 206 3,300 SH   SOLE   0 0 3,300
Shire PLC COM 82481R106 547 3,241 SH   SOLE   457 0 2,784
Snap-On Inc. COM 833034101 63,757 396,696 SH   SOLE   302,054 0 94,642
Southern Co. COM 842587107 242 5,217 SH   SOLE   0 0 5,217
SPS Commerce Inc COM 78463M107 1,218 16,570 SH   SOLE   16,320 0 250
Starbucks Corp COM 855244109 535 10,947 SH   SOLE   0 0 10,947
Stratasys Ltd COM M85548101 339 17,700 SH   SOLE   800 0 16,900
Sysco COM 871829107 292 4,272 SH   SOLE   0 0 4,272
Target COM 87612E106 110,273 1,448,678 SH   SOLE   938,545 0 510,132
TCF Financial COM 872275102 811 32,926 SH   SOLE   3,828 0 29,098
Tennant Company COM 880345103 93,657 1,185,530 SH   SOLE   998,776 0 186,754
Thermo Fisher Scientific COM 883556102 427 2,060 SH   SOLE   600 0 1,460
Tile Shop Inc COM 88677Q109 7,662 995,110 SH   SOLE   995,110 0 0
Toro COM 891092108 148,145 2,458,831 SH   SOLE   1,849,296 0 609,535
Travelers Cos Inc COM 89417E109 30,766 251,476 SH   SOLE   74,055 0 177,421
Union Pacific COM 907818108 1,277 9,010 SH   SOLE   1,800 0 7,210
United Bankshares Inc. COM 909907107 5,709 156,841 SH   SOLE   156,369 0 472
United Fire Group COM 910340108 10,677 195,872 SH   SOLE   195,872 0 0
United Health Group COM 91324P102 123,990 505,380 SH   SOLE   414,868 0 90,512
United Parcel Service COM 911312106 95,194 896,113 SH   SOLE   614,136 0 281,977
United Technologies COM 913017109 1,803 14,421 SH   SOLE   2,721 0 11,700
Urologix Inc COM 917273104 2 20,000 SH   SOLE   0 0 20,000
US Bancorp COM 902973304 331,535 6,628,043 SH   SOLE   5,176,318 0 1,451,725
Verizon Comm COM 92343V104 6,115 121,549 SH   SOLE   3,443 0 118,106
Visa, Inc COM 92826C839 65,624 495,459 SH   SOLE   391,529 0 103,930
Walgreen Boots Alliance COM 931427108 627 10,450 SH   SOLE   0 0 10,450
Walmart Inc COM 931142103 396 4,621 SH   SOLE   1,700 0 2,921
WEC Energy Group COM 92939U106 476 7,369 SH   SOLE   0 0 7,369
Wells Fargo & Co COM 949746101 137,457 2,479,377 SH   SOLE   1,714,191 0 765,186
Westamerica Bancorporation COM 957090103 303 5,359 SH   SOLE   0 0 5,359
Western Union COM 959802109 39,689 1,952,238 SH   SOLE   1,442,903 0 509,335
Weyerhaeuser COM 962166104 677 18,570 SH   SOLE   3,653 0 14,917
Wintrust Finan Corp COM 97650W108 13,308 152,880 SH   SOLE   152,880 0 0
Workiva Inc COM 98139A105 5,861 240,223 SH   SOLE   240,223 0 0
Xcel Energy Inc. COM 98389B100 12,163 266,274 SH   SOLE   95,963 0 170,311
Zimmer Biomet Holdings COM 98956P102 121,819 1,093,138 SH   SOLE   843,626 0 249,512
Zoetis Inc. COM 98978V103 353 4,140 SH   SOLE   0 0 4,140
iShares Cohen & Steers Reit ET ETF 464287564 201 2,013 SH   SOLE   13 0 2,000
iShares Core S&P 500 ETF ETF 464287200 1,219 4,464 SH   SOLE   0 0 4,464
iShares Core S&P Midcap ETF ETF 464287507 410 2,105 SH   SOLE   0 0 2,105
iShares MSCI EAFE Fd ETF 464287465 503 7,506 SH   SOLE   967 0 6,539
iShares Russell 1000 Growth ETF 464287614 941 6,545 SH   SOLE   0 0 6,545
iShares Russell 1000 Value ETF 464287598 587 4,835 SH   SOLE   100 0 4,735
iShares Russell 2000 ETF ETF 464287655 569 3,475 SH   SOLE   0 0 3,475
iShares Russell Midcap ETF ETF 464287499 729 3,435 SH   SOLE   0 0 3,435
iShares S&P Smallcap ETF 464287887 313 1,655 SH   SOLE   0 0 1,655
iShares Select Div ETF 464287168 731 7,479 SH   SOLE   45 0 7,434
Schwab Intl Eq ETF ETF 808524805 1,659 50,190 SH   SOLE   0 0 50,190
Schwab US Broad Mkt ETF ETF 808524102 2,994 45,370 SH   SOLE   0 0 45,370
SPDR Barclays Cap Conv Sec ETF 78464A359 313 5,900 SH   SOLE   5,000 0 900
SPDR S&P 500 ETF Trust ETF 78462F103 8,797 32,427 SH   SOLE   20,610 0 11,817
Vanguard Dividend App ETF ETF 921908844 326 3,204 SH   SOLE   0 0 3,204
Blackrock Muni Hldgs COM 09253P109 157 11,350 SH   SOLE   11,350 0 0
Blackrock MuniVest COM 09253T101 160 11,450 SH   SOLE   11,450 0 0
Eaton Vance Muni Bond COM 27827X101 315 26,685 SH   SOLE   26,685 0 0
Eaton Vance Muni Bond II COM 27827K109 118 10,000 SH   SOLE   10,000 0 0
Invesco Muni Oppt Tst COM 46132C107 117 10,000 SH   SOLE   10,000 0 0
Nuveen MN Qual Mun Income Fd COM 670734102 553 41,302 SH   SOLE   4,300 0 37,002
Nuveen Muni Value Fd COM 670695105 203 13,000 SH   SOLE   13,000 0 0
Nuveen Quality Muncp Income Fd COM 67066V101 506 38,038 SH   SOLE   27,865 0 10,173
Pimco Muni Income COM 72200W106 251 19,200 SH   SOLE   13,200 0 6,000