Portage County is the state's leader in potato production, and Wisconsin is number three in the nation. The "Central Sands" soil region is why, along with a lot of hard-working people. This is a big-time business. In 2023, the state produced 2.9 billion pounds of potatoes valed at $400 million.

I observed the Dambrowski Farms potato harvest near Shantytown, just a stone's throw north of Portage County, and the Plover River Farms just outside Stevens Point. If you're a kid at heart, watching all these big machines do their ballet out in the fields is more exciting than an old man who is still a boy can handle!

I live close to Plover, so off I went to watch the harvest. I was lucky. The weather was fabulous, and I found the harvest in full motion.

If you want to talk about potatoes in Wisconsin, you've first got to talk about a geologic region known as the "Central Sands." I’ll show two maps in succession. 

The first is the map of the five Geographic Provinces of the state, followed by a map that depicts what some call a "geologic region," others call an “eco-region.”

Broadly speaking, the Central Sands region occupies much, but not all, of the Central Plain Geographic Province, essentially the center of the province, and the center of the state, partly in the Driftless Area, partly on its edges. I have pointed the arrow at the approximate area of the farms I visited in southern Marathon and northern Portage counties.

Wisconsin's Department of Natural Resources (DNR) describes the Central Sands region this way:

"The Central Sand Plains Ecological Landscape, located in central Wisconsin, occurs on a flat, sandy lake plain, and supports agriculture, forestry, recreation, and wildlife management. The Ecological Landscape formed in and around what was once Glacial Lake Wisconsin, which contained glacial meltwater extending over 1.1 million acres at its highest stage. Soils are primarily sandy lake deposits, some with silt-loam loess caps. Sandstone buttes carved by rapid drainage of the glacial lake, or by wave action when they existed as islands in the lake, are distinctive features of this landscape.”

While visiting the Wisconsin farms, I never thought I'd be taken to the Andes in South America, but indeed I was. Potato growing actually started in the Peruvian Andes, at heights of 4,000 - 6,000 ft and higher (up to 10,000 ft) on a plateau today called the Titicaca Plateau that stretches across part of Peru and Bolivia. They are said to have over 7,000 varieties of potatoes in the Andes. This plateau is also referred to as the “Altiplano."

I commend a study of the Alitplano to you, especially students. I suggest you find the similarities and differences between it and the Central Sands of Wisconsin; there are plenty of both.

Wisconsin's cool northern temperatures match those in Peru.  I have read that "The rapid warm-up, low density and lack of organic residue of Wisconsin’s glacial soil allow for less plant disease and vigorous plant growth."

Potatoes like deep, well-drained sandy or silt loam soils the best, and that's what the Central Sands gives them. Loam means soil with roughly an equal proportion of sand, silt, and clay.

Wisconsin produces about 7 percent of total US production, behind Washington (21 percent) and Idaho (28 percent), with over 80,000 acres in production. The states of Wisconsin, Idaho, Washington, Oregon, North Dakota, Minnesota, Maine, and California produce nearly 75% of the total crop.

Portage County is the leader in Wisconsin, followed by Waushara, Langlade, and Adams counties in that order. 

During my exploration in October, I concentrated on the harvest, not the growing, because of the time of year. So my report here mainly talks to the harvest, but I do want to touch on the growing.

The potato tuber is what we're interested in. It is an enlarged portion of an underground stem. One source has said that "potatoes grow underground, but are actually swollen stems, not roots." The swollen stem is the tuber.

Sprouts develop from the eyes of seed tubers and grow upward to emerge from the soil. Potatoes are not grown from seeds. Instead, special potatoes called "seeded potatoes" are planted in the ground, either in carefully cut pieces or whole. These pieces of potato grow stems and roots from the “eye."

Roots then start to develop. Leaves and branch stems develop, and roots continue to build. Tubers begin to develop, and flowers will emerge at the top of the stem. Tuber cells then start to expand as they receive nutrients and become the dominant site for carbohydrates and other nutrients. In the final stages, the vines turn yellow and lose leaves, and the vines die. Tuber growth slows and tuber dry matter content reaches a maximum; the tuber skins set, and the harvest is ready. Interestingly, the potato that is harvested is about 80 percent water and 20 percent solids.

Here's what a potato field that is flowering looks like in the summer (presented by the Wisconsin Potato & Vegetable Growers Association).

Let's start our review of the harvest. I was lucky that the "head-rigger" over at Plover River Farms pointed me to one of his fields under harvest and permitted me to watch, with one proviso --- stay out of the way!

This yellow machine is what's known as a windrower harvester, in this case drawn by a tractor.  The harvester is six feet high, 14 feet wide, and 29 feet long! She weighs almost 14,000 lbs. You need at least 125 horses to pull her. She can handle four rows of potatoes at a time.

The operator was just ready to enter the field when the harvester got jammed by a rock. The operator had to dislodge that from the machine to get her going. He wrestled with it for a bit. So while the soil might be "sands," this particular plot had some rock in it, and they are a nuisance. I will come back to the rock issue later.

Before going on, this machine is a Double L Manufacturing 851 Windrower.  I’ll be referring to her as the "851" for short.

Belts run throughout the machine. Look carefully and  you can see three belts, the one on the far right (front) receives potatoes from the digger and the latter puts them back on the ground out the rear side. 

So, the potatoes are dug up in the front, conveyor-belted to the rear, and kicked out the rear section back onto the ground. Why back on the ground? Hang in there; that's where the ballet comes in!

What's happening here is that the potatoes are being kicked out and falling in line on the ground.

This is a look at how the potatoes are lined up. You see the 851 making her way through the field and leaving a line of potatoes in her wake, with most of the vines cut.

Okay, the potatoes have been dug up, most of the vines have been cut and gathered, and potatoes are on top of the ground instead of under it. What now, coach?

The 851 is out in the field and has already done a bunch of digging. Now this bad-boy kicks into action.

This is a Lenco Pull-Type Potato Harvester, a four-row jobbie, I believe. With the 851 having done her work, this Lenco harvester shoots into action along with a line of trucks that were waiting right behind her. As a former military man, watching all this happen in real time was like watching the Army's heavy armor moving across the battlefield in perfect synchronization,  like a ballet, all this heavy machinery moving and working together, following a script.

The Lenco follows the track of the 851. It looked to me like it scrapes, almost sweeps the ground below, pulling in those rows of potatoes, along with a bunch of other stuff, including leftover dead vines. All this stuff then hits belts in the front and makes its way to the trucks, which are traveling along the side of this monster, almost like an Air Force “wing-man."

Here's the formation I was talking about earlier. The 851 "flying lead" is digging up the potatoes and laying them down in nice, neat rows, lying in a slight trough. He's followed by the Lenco sweeping them up and conveying them into a truck "flying on his starboard wing." When that truck is full, another pulls in to replace it. Yes, a ballet of heavy machinery.

The 851 digs up the potatoes and rocks, and the Lenco scarfs them up. It  has a way of determining the rocks, and lays them down in rows. Another group of machines then comes along to pick up the rocks, convey them into trucks, and dump them elsewhere. I saw trucks carrying loads of rocks and dumping them into large piles out of the way. It would be interesting to know what they do with those rocks.

Rocks in the soil have been a problem in this region for some time. While the soil is good for potatoes, the last great glacier in this area left behind many stones and boulders. If you go back to the map of the geographic provinces, you will see that this location happens to be on the edge of the Driftless Area, which means it is on the edge of where the glacier ended. Remember, the glacier did not go into the Driftless Area. Since the leading edge of the glacier covered this area, it stands to reason that the glacier would drop a lot of rock here as it receded, came back, receded, etc.

Early on, these rocks made the soil hard to work. In the "old days," that made the land cheap to buy, which in turn made it easier to buy for immigrant families from Poland, Germany, and elsewhere in Europe. Poles and Germans were among the first and most populous peoples to settle in this section of Portage County.

Here's what the field looks like when these harvesters and truckers are done.

I am going to shift gears now. They’ve got the potatoes dug up, swept up, and loaded into trucks. Now they ave to get the truckloads to storage. To show this, I am going to move away from Plover River Farms, which is a huge operation, to Dambrowski Farms, a smaller operation, over in Shantytown.

The day I was traveling around this region, the highways were filled with potato trucks, making their journeys to the fields being harvested and then back to the various storage areas. In this case, I am at Dambrowski Farm's storage area.

Truck after truck arrives filled with potatoes, and these drivers, probably paid by the number of loads they deliver, don't want to hang around. They want their loads unloaded, and then beat feet back to the fields to get more. So at the Dambrowski Farm storage area, they worked to get the truck unloaded, and, while we were there, just as they did, the next full truck arrived. 

The ballet!

This is a view  of the trucks used to carry the harvest. The sides of the truck's topside are vertical to the ground to gain maximum volume for the potatoes, but the bottom sides angle inward. You lose volume with this design, but the potatoes will flow out nicely when the truck gets to storage.

There are a lot of potatoes in a fully loaded truck; the load is heavy, and the truck is designed to cause the potatoes to want to roll out the back. So, you need a well-designed mechanism to avoid bruising the potatoes and cutting up their skins any more than has already been done during the harvest. 

The potatoes flow off the truck onto a conveyor system that separates the large from the small and gets the larger ones into a storage shed, the smaller ones into a waiting truck.

There is a mechanism that separates the small from the large potatoes. The  small potatoes  fall into a  bin and go up another conveyor into a waiting truck.

This is a good shot of the larger potatoes coming off the truck and onto Dambrowski's belt system. The worker here is picking out the bad ones and small ones missed by the automated system.

You can see how the conveyor belt heads straight into the shed, which is a good-sized shed. 

The worker at the end of the line made  sure the potatoes get up the conveyor belt to the "pile" inside the shed, and adjusted the belt mechanisms so they roll the potatoes off into the pile where she wants them. 

In this instance, she has the conveyor belt dumping them way to the rear and off to the left. The yellow arrow points to the belt stretching toward the left. You can see that the more recently harvested potatoes are on top; they are a darker color, more damp than the others.

Here you can see the belt mechanism that I pointed to in the previous photo, putting the newly harvested potatoes coming off the line to the far left. There is clearance to keep swinging that belt mechanism to the right to add more over there. I do not believe they will pile the potatoes above the wooden trusses forming the roof.

Those potatoes, more appropriately called "tubers," are alive. They are living organisms. As a result, they produce heat and they lose moisture. Remember, I said that potatoes are 80 percent water and only 20 percent solids. So if you're not careful, you're going to lose a bundle of water and end up with ugly, un-marketable shrunken potatoes. Throughout, the potatoes have to go through a curing process.

The most significant shrinkage occurs after harvest and before curing is complete. Despite precautions during the harvest, the potatoes do take a bit of a beating. Wounds speed the escape of moisture, and, of course, can lead to disease. Mother Nature doesn't fool around, though, and takes all this into account.

There is a natural process of healing known as suberization; suberin is a natural waxy substance present in the cell walls of the potato's corky tissues that forms to mend the wound. Indeed, initial storage seeks to give the potatoes time to heal, which is essential if the potatoes are to be stored for a long time. Suberization prospers with the correct temperatures, so temperature control is crucial while they are in storage.

The most common types of storage buildings used are concrete, wood stud and pole frame, and quonset hut. They need to be designed so they can withstand not only the weather outside, but also the force and weight of the potatoes inside. Ventilation is critical to maintain the correct temperature, relative humidity, and air quality.

I also commend a fun website to your attention, that of the Potato Museum Online.

And, oh yes, ma, pass the potatoes!