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
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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
Abbott Laboratories COM 002824100 243,869 4,570,254 SH   SOLE   3,548,081 0 1,022,173
Abbvie Inc COM 00287Y109 17,605 198,125 SH   SOLE   49,490 0 148,635
Actuant Corp COM 00508X203 11,524 450,145 SH   SOLE   450,145 0 0
Adobe Systems COM 00724F101 343 2,300 SH   SOLE   0 0 2,300
Agree Realty Corp COM 008492100 9,816 199,999 SH   SOLE   198,499 0 1,500
ALLETE, Inc. COM 018522300 22,672 293,340 SH   SOLE   231,190 0 62,150
Alliant Energy Corp. COM 018802108 300 7,228 SH   SOLE   0 0 7,228
Alphabet Inc Cl A COM 02079K305 898 922 SH   SOLE   24 0 898
Alphabet Inc Cl C COM 02079K107 166,653 173,758 SH   SOLE   148,703 0 25,055
Altria Group Inc COM 02209S103 575 9,074 SH   SOLE   0 0 9,074
Amazon Com Inc COM 023135106 412 429 SH   SOLE   0 0 429
American Express COM 025816109 112,849 1,247,502 SH   SOLE   947,752 0 299,750
Ameriprise Financial COM 03076C106 333 2,241 SH   SOLE   0 0 2,241
Amgen COM 031162100 1,516 8,129 SH   SOLE   0 0 8,129
Apogee Enterprises, Inc COM 037598109 14,856 307,830 SH   SOLE   306,830 0 1,000
Apple Computer COM 037833100 2,721 17,657 SH   SOLE   95 0 17,562
Applied Materials Inc COM 038222105 434 8,327 SH   SOLE   0 0 8,327
Assoc Banc Corp COM 045487105 76,257 3,144,615 SH   SOLE   2,652,940 0 491,675
AT&T COM 00206R102 1,658 42,336 SH   SOLE   0 0 42,336
Autoliv Inc COM 052800109 286 2,314 SH   SOLE   0 0 2,314
Automatic Data Proc COM 053015103 740 6,767 SH   SOLE   0 0 6,767
Badger Meter Inc COM 056525108 91,862 1,874,743 SH   SOLE   1,429,138 0 445,605
Bank Mutual Corp. COM 063750103 2,532 249,453 SH   SOLE   249,453 0 0
Bank of America Corp COM 060505104 330 13,025 SH   SOLE   0 0 13,025
Baxter International COM 071813109 73,198 1,166,500 SH   SOLE   775,946 0 390,554
Becton Dickinson COM 075887109 854 4,356 SH   SOLE   1,367 0 2,989
Bemis COM 081437105 202,438 4,442,344 SH   SOLE   3,335,111 0 1,107,233
Berkshire Hathaway COM 084670108 2,747 10 SH   SOLE   0 0 10
Berkshire Hathaway B COM 084670702 2,941 16,044 SH   SOLE   0 0 16,044
Bio-Techne Corp COM 09073M104 174,623 1,444,480 SH   SOLE   1,130,484 0 313,996
Biogen Inc. COM 09062X103 330 1,053 SH   SOLE   0 0 1,053
Black Hills Corp COM 092113109 10,039 145,770 SH   SOLE   145,770 0 0
Boeing COM 097023105 833 3,278 SH   SOLE   0 0 3,278
BP PLC COM 055622104 1,105 28,741 SH   SOLE   2,334 0 26,407
Bristol-Myers Squibb COM 110122108 21,662 339,845 SH   SOLE   199,725 0 140,120
Buffalo Wild Wings Inc COM 119848109 2,149 20,335 SH   SOLE   20,290 0 45
C H Robinson Worldwide COM 12541W209 162,283 2,132,496 SH   SOLE   1,630,222 0 502,274
Cardinal Health COM 14149Y108 230 3,434 SH   SOLE   1,458 0 1,976
Cardiovascular Sys Inc COM 141619106 2,133 75,762 SH   SOLE   72,562 0 3,200
Casey's General Stores COM 147528103 12,663 115,700 SH   SOLE   115,700 0 0
Catalent, Inc. COM 148806102 13,683 342,760 SH   SOLE   342,760 0 0
Caterpillar COM 149123101 918 7,362 SH   SOLE   0 0 7,362
Centerpoint Energy Inc COM 15189T107 232 7,959 SH   SOLE   0 0 7,959
Cerner Corp COM 156782104 443 6,205 SH   SOLE   0 0 6,205
Charles Schwab COM 808513105 13,207 301,938 SH   SOLE   60,598 0 241,340
Chevron Corp COM 166764100 43,171 367,416 SH   SOLE   169,548 0 197,868
Chubb Limited Com COM H1467J104 203 1,424 SH   SOLE   1,000 0 424
Cigna Corp COM 125509109 852 4,559 SH   SOLE   0 0 4,559
Cisco COM 17275R102 926 27,535 SH   SOLE   0 0 27,535
Clorox COM 189054109 246 1,863 SH   SOLE   1,700 0 163
Coca-Cola COM 191216100 797 17,701 SH   SOLE   4,325 0 13,376
Colgate-Palmolive COM 194162103 681 9,349 SH   SOLE   0 0 9,349
Comcast New Cl A COM 20030N101 258 6,710 SH   SOLE   0 0 6,710
ConocoPhillips COM 20825C104 9,037 180,564 SH   SOLE   25,482 0 155,082
Consolidated Comm Hldgs COM 209034107 241 12,632 SH   SOLE   0 0 12,632
CoreSite Realty Corp COM 21870Q105 11,112 99,300 SH   SOLE   99,300 0 0
Corning COM 219350105 73,625 2,460,744 SH   SOLE   1,886,072 0 574,672
Costco Wholesale COM 22160K105 493 3,002 SH   SOLE   600 0 2,402
Cray Inc COM 225223304 56,005 2,879,433 SH   SOLE   2,267,248 0 612,185
CSX Corporation COM 126408103 499 9,200 SH   SOLE   0 0 9,200
Cullen Frost Bankers COM 229899109 12,754 134,370 SH   SOLE   134,170 0 200
CVS Health Corp COM 126650100 223 2,743 SH   SOLE   0 0 2,743
CyberOptics Corp COM 232517102 3,156 194,200 SH   SOLE   194,200 0 0
Deluxe Corp COM 248019101 5,357 73,425 SH   SOLE   600 0 72,825
Disney COM 254687106 195,891 1,987,332 SH   SOLE   1,545,073 0 442,259
Dominion Energy, Inc. COM 25746U109 303 3,936 SH   SOLE   0 0 3,936
Donaldson COM 257651109 245,195 5,337,294 SH   SOLE   4,018,182 0 1,319,112
DowDupont Inc. COM 26078J100 1,040 15,025 SH   SOLE   0 0 15,025
Ecolab Inc COM 278865100 358,082 2,784,245 SH   SOLE   2,100,683 0 683,562
EMC Insurance Group COM 268664109 5,498 195,328 SH   SOLE   195,328 0 0
Emerson Electric COM 291011104 42,263 672,550 SH   SOLE   189,837 0 482,713
Exelon Corp COM 30161N101 525 13,928 SH   SOLE   0 0 13,928
Exxon Mobil COM 30231G102 66,807 814,916 SH   SOLE   306,695 0 508,221
Facebook Inc Class A COM 30303M102 285 1,669 SH   SOLE   0 0 1,669
Fastenal Co. COM 311900104 130,864 2,871,088 SH   SOLE   2,135,225 0 735,863
Fedex Corp. COM 31428X106 790 3,501 SH   SOLE   0 0 3,501
Fiserv COM 337738108 137,526 1,066,424 SH   SOLE   788,500 0 277,924
Generac Hldgs COM 368736104 44,436 967,465 SH   SOLE   847,195 0 120,270
General Electric COM 369604103 105,759 4,373,840 SH   SOLE   2,979,982 0 1,393,858
General Mills COM 370334104 176,979 3,419,231 SH   SOLE   2,446,177 0 973,054
Gentherm Inc COM 37253A103 26,008 700,075 SH   SOLE   645,105 0 54,970
Glacier Bancorp Inc COM 37637Q105 16,925 448,220 SH   SOLE   448,220 0 0
Graco Inc COM 384109104 320,726 2,592,983 SH   SOLE   1,872,769 0 720,214
Great Western Bancorp Inc. COM 391416104 87,460 2,118,690 SH   SOLE   1,773,620 0 345,070
Hawkins Chemical COM 420261109 6,920 169,600 SH   SOLE   163,100 0 6,500
HB Fuller COM 359694106 187,903 3,236,359 SH   SOLE   2,670,140 0 566,219
Hershey COM 427866108 5,981 54,785 SH   SOLE   52,170 0 2,615
Home Depot COM 437076102 60,006 366,873 SH   SOLE   204,995 0 161,878
Honeywell Inc COM 438516106 322,278 2,273,729 SH   SOLE   1,672,320 0 601,409
Hormel COM 440452100 218,995 6,813,785 SH   SOLE   5,204,806 0 1,608,979
Hub Group Inc Cl A COM 443320106 9,835 228,980 SH   SOLE   228,980 0 0
IBM COM 459200101 24,822 171,092 SH   SOLE   81,998 0 89,094
IDEXX Laboratories, Inc COM 45168D104 715 4,598 SH   SOLE   0 0 4,598
Illinois Tool Works Inc COM 452308109 625 4,226 SH   SOLE   0 0 4,226
Intel COM 458140100 15,715 412,693 SH   SOLE   60,622 0 352,071
Intl Flavors/Fragr COM 459506101 362 2,531 SH   SOLE   2,000 0 531
IPG Photonics Corp COM 44980X109 370 2,000 SH   SOLE   0 0 2,000
J.P. Morgan Chase & Co COM 46625H100 26,512 277,580 SH   SOLE   165,930 0 111,650
Johnson & Johnson COM 478160104 287,244 2,209,403 SH   SOLE   1,625,331 0 584,072
Kellogg COM 487836108 265 4,250 SH   SOLE   0 0 4,250
Kimberly-Clark COM 494368103 25,338 215,316 SH   SOLE   85,195 0 130,121
Lilly (Eli) COM 532457108 83,568 976,949 SH   SOLE   693,310 0 283,639
Lockheed Martin Corp COM 539830109 268 864 SH   SOLE   494 0 370
Lowes Companies Inc COM 548661107 429 5,369 SH   SOLE   0 0 5,369
Marcus Corp. COM 566330106 7,998 288,723 SH   SOLE   288,723 0 0
Marsh & McLennan COM 571748102 282 3,366 SH   SOLE   1,900 0 1,466
McDonald's Corp COM 580135101 2,358 15,051 SH   SOLE   10,325 0 4,726
MDU Resources Group COM 552690109 4,992 192,370 SH   SOLE   60,480 0 131,890
Medtronic COM G5960L103 276,399 3,554,055 SH   SOLE   2,673,399 0 880,656
Merck & Co Inc COM 58933Y105 5,648 88,203 SH   SOLE   8,100 0 80,103
Microsoft COM 594918104 11,424 153,369 SH   SOLE   24,810 0 128,559
MMM Co. COM 88579Y101 328,244 1,563,810 SH   SOLE   1,022,406 0 541,404
MTS Systems COM 553777103 2,436 45,570 SH   SOLE   2,300 0 43,270
NextEra Energy, Inc. COM 65339F101 401 2,735 SH   SOLE   0 0 2,735
Nike COM 654106103 228 4,400 SH   SOLE   1,200 0 3,200
Norfolk Southern Corp COM 655844108 743 5,615 SH   SOLE   0 0 5,615
Novartis COM 66987V109 322 3,750 SH   SOLE   1,300 0 2,450
NVE Corp COM 629445206 34,132 432,219 SH   SOLE   373,921 0 58,298
NW Biotherapeutics COM 66737P600 2 12,500 SH   SOLE   0 0 12,500
Oasis Petroleum Inc COM 674215108 2,916 319,720 SH   SOLE   319,720 0 0
Oracle Sys COM 68389X105 1,578 32,643 SH   SOLE   0 0 32,643
Oshkosh Corp COM 688239201 15,580 188,757 SH   SOLE   188,690 0 67
Otter Tail Power COM 689648103 304 7,008 SH   SOLE   0 0 7,008
Patterson Companies COM 703395103 90,251 2,335,095 SH   SOLE   1,808,763 0 526,332
Paychex COM 704326107 263 4,391 SH   SOLE   0 0 4,391
Pentair PLC COM G7S00T104 180,849 2,661,115 SH   SOLE   1,949,644 0 711,471
PepsiCo Inc COM 713448108 1,548 13,895 SH   SOLE   400 0 13,495
Pfizer Inc COM 717081103 170,174 4,766,771 SH   SOLE   3,601,189 0 1,165,582
Philip Morris Intl Inc COM 718172109 1,002 9,030 SH   SOLE   0 0 9,030
Phillips 66 COM 718546104 2,157 23,547 SH   SOLE   0 0 23,547
Physicians Realty Tr COM 71943U104 16,110 908,610 SH   SOLE   890,610 0 18,000
Polaris Ind COM 731068102 419 4,008 SH   SOLE   0 0 4,008
Praxair COM 74005P104 287 2,051 SH   SOLE   0 0 2,051
Premier Inc Cl A COM 74051N102 10,111 310,439 SH   SOLE   310,439 0 0
Principal Financial COM 74251V102 166,799 2,592,454 SH   SOLE   1,983,720 0 608,734
Procter & Gamble COM 742718109 30,827 338,829 SH   SOLE   60,422 0 278,407
Proto Labs COM 743713109 39,584 492,952 SH   SOLE   409,745 0 83,207
PureCycle Corp COM 746228303 89 11,855 SH   SOLE   0 0 11,855
QCR Holdings COM 74727A104 3,994 87,775 SH   SOLE   87,775 0 0
Qualcomm, Inc. COM 747525103 79,228 1,528,324 SH   SOLE   1,243,738 0 284,586
Raven Industries Inc COM 754212108 5,413 167,066 SH   SOLE   166,566 0 500
Raytheon Co COM 755111507 268 1,435 SH   SOLE   0 0 1,435
Roche Hldg Ltd ADR COM 771195104 172,218 5,381,813 SH   SOLE   4,412,462 0 969,351
Royal Dutch Shell Spons ADR A COM 780259206 383 6,320 SH   SOLE   400 0 5,920
Schlumberger COM 806857108 159,362 2,284,428 SH   SOLE   1,764,125 0 520,303
SEI Investments Co COM 784117103 201 3,300 SH   SOLE   0 0 3,300
Shire PLC COM 82481R106 1,996 13,036 SH   SOLE   350 0 12,686
Snap-On Inc. COM 833034101 56,437 378,745 SH   SOLE   284,048 0 94,697
SPS Commerce Inc COM 78463M107 3,339 58,870 SH   SOLE   58,620 0 250
Starbucks Corp COM 855244109 625 11,634 SH   SOLE   0 0 11,634
Stratasys Ltd COM M85548101 20,290 877,600 SH   SOLE   733,713 0 143,887
Sysco COM 871829107 257 4,765 SH   SOLE   0 0 4,765
Target COM 87612E106 122,105 2,069,222 SH   SOLE   1,394,181 0 675,041
TCF Financial COM 872275102 591 34,654 SH   SOLE   0 0 34,654
Tennant Company COM 880345103 64,836 979,403 SH   SOLE   796,491 0 182,912
Texas Instruments COM 882508104 296 3,300 SH   SOLE   2,000 0 1,300
Thermo Fisher Scientific COM 883556102 297 1,570 SH   SOLE   0 0 1,570
Tile Shop Inc COM 88677Q109 8,167 643,110 SH   SOLE   643,110 0 0
Toro COM 891092108 158,723 2,557,573 SH   SOLE   1,853,809 0 703,764
Travelers Cos Inc COM 89417E109 54,250 442,785 SH   SOLE   242,109 0 200,676
Unilever COM 904784709 260 4,400 SH   SOLE   0 0 4,400
Union Pacific COM 907818108 1,123 9,680 SH   SOLE   1,800 0 7,880
United Bankshares Inc. COM 909907107 7,262 195,479 SH   SOLE   195,479 0 0
United Fire Group COM 910340108 11,678 254,872 SH   SOLE   254,872 0 0
United Health Group COM 91324P102 103,414 528,027 SH   SOLE   426,453 0 101,574
United Parcel Service COM 911312106 144,584 1,203,965 SH   SOLE   869,511 0 334,454
United Technologies COM 913017109 1,632 14,057 SH   SOLE   1,200 0 12,857
Urologix Inc COM 917273104 0 20,000 SH   SOLE   0 0 20,000
US Bancorp COM 902973304 354,086 6,607,317 SH   SOLE   5,014,903 0 1,592,414
Verizon Comm COM 92343V104 7,304 147,588 SH   SOLE   5,866 0 141,722
Visa, Inc COM 92826C839 833 7,916 SH   SOLE   0 0 7,916
Walgreen Boots Alliance COM 931427108 1,171 15,164 SH   SOLE   0 0 15,164
WalMart COM 931142103 429 5,496 SH   SOLE   2,000 0 3,496
WEC Energy Group COM 92939U106 470 7,494 SH   SOLE   0 0 7,494
Wells Fargo & Co COM 949746101 157,128 2,849,105 SH   SOLE   1,931,652 0 917,453
Westamerica Bancorporation COM 957090103 319 5,359 SH   SOLE   0 0 5,359
Western Union COM 959802109 92,821 4,834,437 SH   SOLE   3,836,312 0 998,125
Weyerhaeuser COM 962166104 358 10,507 SH   SOLE   3,923 0 6,584
Wintrust Finan Corp COM 97650W108 15,931 203,430 SH   SOLE   203,430 0 0
Workiva Inc COM 98139A105 5,930 284,423 SH   SOLE   284,423 0 0
Xcel Energy Inc. COM 98389B100 13,831 292,284 SH   SOLE   105,635 0 186,649
Zimmer Biomet Holdings, Inc. COM 98956P102 128,388 1,096,486 SH   SOLE   823,345 0 273,141
iShares Cohen & Steers Reit ET ETF 464287564 253 2,515 SH   SOLE   0 0 2,515
iShares Core S&P 500 ETF ETF 464287200 1,167 4,614 SH   SOLE   150 0 4,464
iShares Core S&P Midcap ETF ETF 464287507 381 2,130 SH   SOLE   0 0 2,130
iShares MSCI EAFE Fd ETF 464287465 859 12,539 SH   SOLE   0 0 12,539
iShares Russell 1000 Growth ETF 464287614 819 6,545 SH   SOLE   0 0 6,545
iShares Russell 1000 Value ETF 464287598 561 4,735 SH   SOLE   0 0 4,735
iShares Russell 2000 ETF ETF 464287655 515 3,475 SH   SOLE   0 0 3,475
iShares Russell Midcap ETF ETF 464287499 712 3,610 SH   SOLE   0 0 3,610
iShares S&P Smallcap ETF 464287887 272 1,655 SH   SOLE   0 0 1,655
iShares Select Div ETF 464287168 1,164 12,434 SH   SOLE   0 0 12,434
iShares US Preferred Stock ETF ETF 464288687 213 5,500 SH   SOLE   0 0 5,500
Schwab Intl Eq ETF ETF 808524805 1,339 40,000 SH   SOLE   0 0 40,000
Schwab US Broad Mkt ETF ETF 808524102 2,763 45,370 SH   SOLE   0 0 45,370
SPDR S&P 500 ETF Trust ETF 78462F103 7,467 29,720 SH   SOLE   8,580 0 21,140
Vanguard Dividend App ETF ETF 921908844 304 3,204 SH   SOLE   0 0 3,204
Vanguard Index Total Stk Mkt ETF 922908769 415 3,206 SH   SOLE   0 0 3,206
Eaton Vance Tax Managed Buy Wr COM 27828Y108 199 13,000 SH   SOLE   0 0 13,000
Nuveen MN Qual Mun Income Fd COM 670734102 564 37,002 SH   SOLE   0 0 37,002
Nuveen Quality Muncp Income Fd COM 67066V101 144 10,173 SH   SOLE   0 0 10,173