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 11,359 275,640 SH   SOLE   275,640 0 0
Abbott Laboratories COM 002824100 195,390 2,335,251 SH   SOLE   1,745,160 0 590,090
Abbvie Inc COM 00287Y109 5,740 75,800 SH   SOLE   19,765 0 56,035
Actuant Corp COM 00508X203 8,410 383,300 SH   SOLE   383,300 0 0
Adobe Inc COM 00724F101 568 2,055 SH   SOLE   395 0 1,660
Allete Inc COM 018522300 3,712 42,468 SH   SOLE   13,030 0 29,438
Alliant Energy Corp COM 018802108 303 5,618 SH   SOLE   0 0 5,618
Alphabet Inc Class A COM 02079K305 1,791 1,467 SH   SOLE   1,039 0 428
Alphabet Inc Class C COM 02079K107 359,821 295,177 SH   SOLE   251,946 0 43,231
Amazon Com Inc COM 023135106 823 474 SH   SOLE   129 0 345
Amcor Plc COM G0250X107 32,952 3,379,680 SH   SOLE   1,823,391 0 1,556,289
American Express COM 025816109 159,381 1,347,493 SH   SOLE   1,099,414 0 248,079
American Tower Cl A COM 03027X100 746 3,372 SH   SOLE   227 0 3,145
Ameriprise Financial COM 03076C106 343 2,335 SH   SOLE   1,624 0 711
Ametek Inc COM 031100100 251 2,738 SH   SOLE   2,738 0 0
Amgen COM 031162100 1,699 8,780 SH   SOLE   4,734 0 4,046
ANSYS Inc COM 03662Q105 222 1,001 SH   SOLE   11 0 990
Apogee Enterprises, Inc COM 037598109 12,365 317,140 SH   SOLE   317,040 0 100
Apple Inc COM 037833100 7,895 35,251 SH   SOLE   14,731 0 20,520
Applied Materials Inc COM 038222105 201 4,037 SH   SOLE   60 0 3,977
Assoc Banc Corp COM 045487105 52,805 2,607,664 SH   SOLE   2,294,104 0 313,560
AT&T Inc COM 00206R102 1,631 43,101 SH   SOLE   16,618 0 26,483
Automatic Data Proc COM 053015103 815 5,052 SH   SOLE   3,952 0 1,100
Axogen Inc COM 05463X106 187 15,000 SH   SOLE   15,000 0 0
Badger Meter Inc COM 056525108 44,148 822,124 SH   SOLE   601,180 0 220,944
Bank of America Corp COM 060505104 436 14,955 SH   SOLE   4,390 0 10,565
Baxter International COM 071813109 53,571 612,451 SH   SOLE   404,142 0 208,309
Becton Dickinson & Co COM 075887109 1,093 4,322 SH   SOLE   2,859 0 1,463
Berkshire Hathaway COM 084670108 3,430 11 SH   SOLE   1 0 10
Berkshire Hathaway B COM 084670702 4,613 22,175 SH   SOLE   2,768 0 19,407
Bio-Techne Corp COM 09073M104 203,554 1,040,295 SH   SOLE   841,028 0 199,267
Biogen Inc COM 09062X103 239 1,025 SH   SOLE   750 0 275
Black Hills Corp COM 092113109 11,747 153,100 SH   SOLE   153,100 0 0
Boeing COM 097023105 1,354 3,560 SH   SOLE   1,965 0 1,595
BP PLC COM 055622104 782 20,594 SH   SOLE   10,438 0 10,156
Bristol-Myers Squibb COM 110122108 11,622 229,182 SH   SOLE   154,826 0 74,356
Cabot Microelectronics Corp COM 12709P103 11,588 82,060 SH   SOLE   82,060 0 0
Calyxt Inc COM 13173L107 1,188 210,595 SH   SOLE   210,595 0 0
Cardiovascular Sys Inc COM 141619106 4,721 99,340 SH   SOLE   99,340 0 0
Carrizo Oil & Gas Inc COM 144577103 5,359 624,250 SH   SOLE   624,250 0 0
Casey's General Stores COM 147528103 11,733 72,805 SH   SOLE   72,805 0 0
Catalent Inc COM 148806102 13,648 286,358 SH   SOLE   285,755 0 603
Caterpillar COM 149123101 889 7,040 SH   SOLE   1,612 0 5,428
Celgene Corp COM 151020104 285 2,870 SH   SOLE   0 0 2,870
Centerpoint Energy Inc COM 15189T107 206 6,825 SH   SOLE   535 0 6,290
CH Robinson Worldwide COM 12541W209 177,232 2,090,493 SH   SOLE   1,720,054 0 370,439
Charles Schwab COM 808513105 52,053 1,244,395 SH   SOLE   986,917 0 257,478
Chevron Corp COM 166764100 27,629 232,960 SH   SOLE   122,797 0 110,163
Cisco COM 17275R102 1,657 33,535 SH   SOLE   9,772 0 23,763
Clorox COM 189054109 230 1,513 SH   SOLE   1,513 0 0
Coca-Cola COM 191216100 1,551 28,485 SH   SOLE   10,893 0 17,592
Colgate-Palmolive COM 194162103 535 7,276 SH   SOLE   2,600 0 4,676
Comcast New Cl A COM 20030N101 341 7,562 SH   SOLE   2,394 0 5,168
ConocoPhillips COM 20825C104 5,832 102,360 SH   SOLE   24,081 0 78,279
Core Laboratories NV COM N22717107 39,852 854,821 SH   SOLE   756,296 0 98,525
CoreSite Realty Corp COM 21870Q105 138,561 1,137,145 SH   SOLE   992,525 0 144,620
Corning COM 219350105 69,398 2,433,301 SH   SOLE   1,993,048 0 440,253
Costco Wholesale COM 22160K105 995 3,453 SH   SOLE   1,381 0 2,072
CSX Corporation COM 126408103 523 7,550 SH   SOLE   0 0 7,550
Cullen Frost Bankers COM 229899109 18,184 205,355 SH   SOLE   163,230 0 42,125
CyberOptics Corp COM 232517102 4,201 293,954 SH   SOLE   293,954 0 0
Deere & Co COM 244199105 243 1,442 SH   SOLE   112 0 1,330
Deluxe Corp COM 248019101 1,943 39,522 SH   SOLE   32,208 0 7,314
Digi Int'l Inc COM 253798102 16,927 1,242,790 SH   SOLE   1,209,365 0 33,425
Disney COM 254687106 229,991 1,764,820 SH   SOLE   1,438,985 0 325,835
Dominion Energy, Inc COM 25746U109 377 4,646 SH   SOLE   1,264 0 3,382
Donaldson COM 257651109 246,247 4,728,243 SH   SOLE   3,778,970 0 949,273
Ecolab Inc COM 278865100 347,765 1,756,032 SH   SOLE   1,348,501 0 407,531
Edwards Lifesciences COM 28176E108 290 1,320 SH   SOLE   200 0 1,120
Elanco Animal Health Inc COM 28414H103 23,248 874,318 SH   SOLE   610,308 0 264,010
Emerson Electric COM 291011104 25,598 382,867 SH   SOLE   189,659 0 193,208
Enterprise Prod Ptnrs LP COM 293792107 263 9,200 SH   SOLE   8,600 0 600
Exelon Corp COM 30161N101 407 8,428 SH   SOLE   0 0 8,428
Exxon Mobil COM 30231G102 19,689 278,847 SH   SOLE   119,849 0 158,998
Facebook Inc Class A COM 30303M102 239 1,340 SH   SOLE   1,274 0 66
Fastenal Co COM 311900104 170,853 5,229,660 SH   SOLE   4,146,896 0 1,082,764
FireEye Inc COM 31816Q101 2,796 209,605 SH   SOLE   209,605 0 0
Fiserv COM 337738108 204,594 1,975,032 SH   SOLE   1,543,276 0 431,756
Fleetcor Technologies Inc COM 339041105 287 1,000 SH   SOLE   0 0 1,000
Fluidigm Corp COM 34385P108 46 10,000 SH   SOLE   10,000 0 0
Generac Hldgs COM 368736104 49,699 634,405 SH   SOLE   562,007 0 72,398
General Electric COM 369604103 867 97,011 SH   SOLE   16,225 0 80,786
General Mills COM 370334104 122,412 2,220,822 SH   SOLE   1,578,438 0 642,384
Gentherm Inc COM 37253A103 21,404 520,977 SH   SOLE   480,730 0 40,247
Glacier Bancorp Inc COM 37637Q105 11,846 292,775 SH   SOLE   292,405 0 370
Graco Inc COM 384109104 235,372 5,112,328 SH   SOLE   3,935,057 0 1,177,271
Great Western Bancorp Inc COM 391416104 79,701 2,415,180 SH   SOLE   2,089,040 0 326,140
Hawkins Chemical COM 420261109 2,794 65,737 SH   SOLE   59,237 0 6,500
HB Fuller COM 359694106 127,857 2,746,066 SH   SOLE   2,374,805 0 371,261
Hershey COM 427866108 12,054 77,771 SH   SOLE   68,343 0 9,428
HMS Hldgs Corp COM 40425J101 207 6,010 SH   SOLE   0 0 6,010
Home Depot COM 437076102 67,012 288,822 SH   SOLE   177,375 0 111,447
Honeywell Inc COM 438516106 216,180 1,277,658 SH   SOLE   910,716 0 366,942
Hormel COM 440452100 241,876 5,531,125 SH   SOLE   4,488,871 0 1,042,254
Hub Group Inc Cl A COM 443320106 12,270 263,875 SH   SOLE   263,875 0 0
IBM COM 459200101 5,720 39,335 SH   SOLE   27,399 0 11,936
IDEXX Laboratories, Inc COM 45168D104 923 3,394 SH   SOLE   400 0 2,994
Illinois Tool Works Inc COM 452308109 415 2,649 SH   SOLE   1,450 0 1,199
Inspire Medical Systems Inc COM 457730109 9,593 157,215 SH   SOLE   156,040 0 1,175
Intel COM 458140100 19,260 373,772 SH   SOLE   131,912 0 241,860
Interpace Diagnostics Group COM 46062X204 40 50,000 SH   SOLE   50,000 0 0
Intl Flavors/Fragr COM 459506101 303 2,466 SH   SOLE   2,466 0 0
Intricon Corp Com COM 46121H109 5,673 291,816 SH   SOLE   291,816 0 0
IPG Photonics Corp COM 44980X109 203 1,500 SH   SOLE   0 0 1,500
J P Morgan Chase & Co COM 46625H100 28,880 245,393 SH   SOLE   160,992 0 84,401
Johnson & Johnson COM 478160104 262,571 2,029,458 SH   SOLE   1,609,941 0 419,517
Kellogg COM 487836108 275 4,268 SH   SOLE   1,718 0 2,550
Kimberly-Clark COM 494368103 15,967 112,405 SH   SOLE   52,211 0 60,194
Lilly (Eli) COM 532457108 80,803 722,553 SH   SOLE   516,945 0 205,608
Littelfuse Inc COM 537008104 90,072 507,990 SH   SOLE   419,562 0 88,428
Lockheed Martin Corp COM 539830109 236 606 SH   SOLE   170 0 436
Lowes Companies Inc COM 548661107 810 7,369 SH   SOLE   2,751 0 4,618
Marcus Corp COM 566330106 9,557 258,238 SH   SOLE   258,238 0 0
MasterCard Inc COM 57636Q104 681 2,509 SH   SOLE   114 0 2,395
McCormick & Co COM 579780206 211 1,350 SH   SOLE   600 0 750
McDonald's Corp COM 580135101 3,389 15,786 SH   SOLE   12,167 0 3,619
MDU Resources Group COM 552690109 1,803 63,943 SH   SOLE   19,758 0 44,185
Medtronic COM G5960L103 322,904 2,972,785 SH   SOLE   2,354,532 0 618,253
Merck & Co Inc COM 58933Y105 6,774 80,465 SH   SOLE   28,528 0 51,937
MGP Ingredients Inc COM 55303J106 5,360 107,900 SH   SOLE   107,900 0 0
Microsoft COM 594918104 236,192 1,698,855 SH   SOLE   1,444,357 0 254,498
MMM Co COM 88579Y101 314,295 1,911,770 SH   SOLE   1,454,012 0 457,758
Mondelez Intl Cl A COM 609207105 241 4,364 SH   SOLE   3,085 0 1,279
Motorola Solutions Inc COM 620076307 51,716 303,477 SH   SOLE   285,203 0 18,274
MTS Systems COM 553777103 1,771 32,046 SH   SOLE   10,121 0 21,925
Nestle S A Reg B ADR COM 641069406 266 2,450 SH   SOLE   1,550 0 900
NextEra Energy, Inc COM 65339F101 386 1,656 SH   SOLE   472 0 1,184
Nike COM 654106103 413 4,400 SH   SOLE   1,450 0 2,950
Norfolk Southern Corp COM 655844108 753 4,190 SH   SOLE   480 0 3,710
Northwestern Corp New COM 668074305 3,602 47,990 SH   SOLE   47,990 0 0
Novartis COM 66987V109 252 2,900 SH   SOLE   700 0 2,200
NVE Corp COM 629445206 28,524 429,908 SH   SOLE   373,706 0 56,202
nVent Electric PLC COM G6700G107 68,457 3,106,039 SH   SOLE   2,590,663 0 515,376
NVIDIA Corp COM 67066G104 72,561 416,851 SH   SOLE   376,936 0 39,915
NW Biotherapeutics COM 66737P600 3 12,500 SH   SOLE   0 0 12,500
Oasis Petroleum Inc COM 674215108 3,164 914,455 SH   SOLE   914,455 0 0
Old Natl Bancorp Ind Com COM 680033107 63,127 3,669,112 SH   SOLE   3,274,672 0 394,440
Oracle Sys COM 68389X105 1,489 27,049 SH   SOLE   547 0 26,502
Orocobre Ltd COM Q7142R106 57 33,000 SH   SOLE   33,000 0 0
Oshkosh Corp COM 688239201 13,981 184,450 SH   SOLE   184,450 0 0
Pareteum Corp COM 69946T207 26 20,000 SH   SOLE   20,000 0 0
Patterson Companies COM 703395103 9,024 506,372 SH   SOLE   404,454 0 101,918
Paychex COM 704326107 218 2,630 SH   SOLE   1,642 0 988
Pentair PLC COM G7S00T104 58,552 1,548,991 SH   SOLE   1,097,331 0 451,660
PepsiCo Inc COM 713448108 1,971 14,377 SH   SOLE   6,085 0 8,292
Pfizer Inc COM 717081103 101,202 2,816,642 SH   SOLE   2,151,146 0 665,496
Philip Morris Intl Inc COM 718172109 404 5,315 SH   SOLE   2,130 0 3,185
Phillips 66 COM 718546104 2,111 20,611 SH   SOLE   7,484 0 13,127
Physicians Realty Tr COM 71943U104 8,440 475,515 SH   SOLE   456,215 0 19,300
Plug Power Inc COM 72919P202 79 30,000 SH   SOLE   30,000 0 0
Polaris Inc COM 731068102 202 2,292 SH   SOLE   2,142 0 150
Polymet Mining Corp COM 731916102 140 436,669 SH   SOLE   436,669 0 0
Premier Inc Cl A COM 74051N102 8,334 288,159 SH   SOLE   288,159 0 0
Principal Financial COM 74251V102 164,328 2,875,885 SH   SOLE   2,367,731 0 508,154
Procter & Gamble COM 742718109 26,211 210,735 SH   SOLE   73,116 0 137,619
Proto Labs COM 743713109 23,574 230,894 SH   SOLE   185,378 0 45,516
PureCycle Corp COM 746228303 122 11,855 SH   SOLE   0 0 11,855
QCR Holdings COM 74727A104 5,342 140,660 SH   SOLE   140,660 0 0
Qualcomm, Inc COM 747525103 96,214 1,261,333 SH   SOLE   1,098,124 0 163,209
Raven Industries Inc COM 754212108 7,845 234,461 SH   SOLE   233,961 0 500
Raytheon Co COM 755111507 271 1,381 SH   SOLE   481 0 900
Resideo Technologies COM 76118Y104 201 14,010 SH   SOLE   7,078 0 6,932
Roche Hldg Ltd ADR COM 771195104 197,599 5,421,098 SH   SOLE   4,723,350 0 697,748
Rockwell Automation COM 773903109 5,279 32,030 SH   SOLE   30,720 0 1,310
Rockwell Med Inc COM 774374102 55 20,000 SH   SOLE   20,000 0 0
Royal Dutch Shell Spons ADR A COM 780259206 300 5,095 SH   SOLE   775 0 4,320
Schlumberger COM 806857108 44,006 1,287,847 SH   SOLE   875,263 0 412,584
Sherwin Williams Co COM 824348106 29,350 53,376 SH   SOLE   44,292 0 9,084
Snap-On Inc COM 833034101 11,364 72,596 SH   SOLE   26,380 0 46,216
Southern Co COM 842587107 273 4,417 SH   SOLE   1,659 0 2,758
Starbucks Corp COM 855244109 838 9,475 SH   SOLE   9,345 0 130
Surmodics Inc COM 868873100 1,345 29,398 SH   SOLE   28,098 0 1,300
Sysco COM 871829107 379 4,772 SH   SOLE   3,172 0 1,600
Target COM 87612E106 86,427 808,408 SH   SOLE   533,239 0 275,168
TCF Financial COM 872307103 578 15,182 SH   SOLE   7,365 0 7,817
Tennant Company COM 880345103 99,840 1,412,167 SH   SOLE   1,240,301 0 171,866
The Blackstone Inc COM 09260D107 486 9,950 SH   SOLE   9,950 0 0
Thermo Fisher Scientific COM 883556102 513 1,760 SH   SOLE   300 0 1,460
Tile Shop Inc COM 88677Q109 2,093 656,125 SH   SOLE   656,125 0 0
Toro COM 891092108 199,557 2,722,467 SH   SOLE   2,222,566 0 499,901
Travelers Cos Inc COM 89417E109 33,582 225,853 SH   SOLE   107,937 0 117,916
Union Pacific COM 907818108 1,370 8,459 SH   SOLE   1,900 0 6,559
United Bankshares Inc COM 909907107 4,237 111,889 SH   SOLE   111,889 0 0
United Fire Group COM 910340108 8,052 171,392 SH   SOLE   171,392 0 0
United Health Group COM 91324P102 169,829 781,469 SH   SOLE   675,339 0 106,130
United Parcel Service COM 911312106 60,561 505,429 SH   SOLE   276,015 0 229,414
United Technologies COM 913017109 1,742 12,761 SH   SOLE   5,538 0 7,223
US Bancorp COM 902973304 363,170 6,562,520 SH   SOLE   5,355,975 0 1,206,545
Vericel Corp COM 92346J108 151 10,000 SH   SOLE   10,000 0 0
Verizon Comm COM 92343V104 6,972 115,505 SH   SOLE   26,241 0 89,264
Visa, Inc COM 92826C839 115,170 669,556 SH   SOLE   560,485 0 109,071
Walgreen Boots Alliance COM 931427108 468 8,465 SH   SOLE   1,015 0 7,450
Walmart Inc COM 931142103 545 4,596 SH   SOLE   3,150 0 1,446
WEC Energy Group COM 92939U106 696 7,319 SH   SOLE   0 0 7,319
Wells Fargo & Co COM 949746101 116,823 2,316,086 SH   SOLE   1,806,010 0 510,076
Westamerica Bancorporation COM 957090103 333 5,359 SH   SOLE   5,359 0 0
Western Union COM 959802109 352 15,209 SH   SOLE   4,400 0 10,809
Weyerhaeuser COM 962166104 476 17,169 SH   SOLE   5,154 0 12,015
Wintrust Finan Corp COM 97650W108 14,426 223,205 SH   SOLE   223,205 0 0
Workiva Inc COM 98139A105 5,489 125,243 SH   SOLE   125,243 0 0
Xcel Energy Inc COM 98389B100 15,587 240,200 SH   SOLE   124,739 0 115,461
Zimmer Biomet Holdings COM 98956P102 133,589 973,182 SH   SOLE   775,059 0 198,123
Zoetis Inc COM 98978V103 482 3,868 SH   SOLE   1,928 0 1,940
AMEX Technology SPDR ETF 81369Y803 222 2,752 SH   SOLE   1,052 0 1,700
iShares Core S&P 500 ETF ETF 464287200 1,258 4,214 SH   SOLE   415 0 3,799
iShares Core S&P Midcap ETF ETF 464287507 363 1,880 SH   SOLE   0 0 1,880
iShares MSCI EAFE Fd ETF 464287465 407 6,239 SH   SOLE   0 0 6,239
iShares S&P Smallcap ETF 464287887 295 1,655 SH   SOLE   0 0 1,655
Schwab Intl Eq ETF ETF 808524805 1,599 50,190 SH   SOLE   0 0 50,190
Schwab US Broad Mkt ETF ETF 808524102 3,222 45,370 SH   SOLE   15,510 0 29,860
SPDR S&P 500 ETF Trust ETF 78462F103 4,683 15,780 SH   SOLE   8,796 0 6,984
Vanguard Dividend App ETF ETF 921908844 383 3,204 SH   SOLE   959 0 2,245
Eaton Vance Muni Bond COM 27827X101 134 10,316 SH   SOLE   10,316 0 0
Nuveen MN Qual Mun Income Fd COM 670734102 529 37,002 SH   SOLE   5,802 0 31,200