Cultivator set up with disc hillers.

Fjordworks: Horse Powered Potatoes Part Two

by Stephen Leslie with technical assistance provided by Kerry Gawalt, both of Cedar Mountain Farm at Cobb Hill co-housing in Hartland, VT.

Introduction

On our farm all the crops in our 4 acre market garden are planted and cultivated on the flat (no bed or ridge forming). This simplified approach allows us to cultivate crops with very few changes necessary to the set-up of attachments on the riding cultivator. This kind of streamlining is important because we are a diversified farm, managing intensively grazed dairy cows and extensive hay land, so the labor pool can sometimes get spread pretty thin. We have a second riding cultivator that is set-up for hilling corn, leeks, and potatoes. We commit a 1/4 acre section to potatoes each year (this year 18 rows in a plot measuring roughly 60’ x 180’). In the past we found that a potato section of this size can be very effectively hilled with a single-horse drawn hiller (variously known as a middle-buster or potato plow). More recently we shifted to using disc hiller attachments on the riding cultivator. The advantage with this set up is that the attachments can be set at successively wider spacing for a second and even third hilling. Our potatoes are planted on a 36” row spacing to accommodate our horse drawn potato digger. The cultivator that we use for hilling the potatoes is set up with a 48” wheel base which gives us an ample comfort zone to work in by allowing a 24” margin on either side of the row of potatoes upon which to set up the gangs of the cultivator with discs, shovels, and sweeps. At the end of Part One we had completed our first disc hilling with the riding cultivator. This was followed up by two more successive hillngs at 7-10 day intervals. For the 2nd and 3rd hilling we adjusted the shanks of the disc hiller attachments from the upfront and innermost position on the gangs to the further back middle position (from 24” to 32”) to accommodate the burgeoning foliage and to insure that the discs were not cutting into the root zone.

Disc hiller attachments in the potato patch at Orchard Hill Farm – photo courtesy of Ken Laing

A week or so after the final hilling a weed bloom sprouted in the trough between rows. We thought the riding cultivator might be too aggressive and undo the sides of the hills, so we went through the patch with the single horse walk behind cultivator set to its narrowest width (about 15”). This tool did a good job of cultivating the trough without disturbing the hills or “pruning” the root zone of the spuds. At this point we had done all we could to create optimal growing conditions for the potatoes. Now it was up to the vicissitudes of weather to determine the success of our harvest.

Ann Siri’s “All-In-One” tool used to hill potatoes – photo courtesy of Walt Bernard

Water

It is pretty remarkable to consider that even as nutritionally concentrated a food staple as the potato is it is about 90% water. Typical of most vegetable crops, potatoes require about 1” of rain (or supplemental irrigation) per week to maintain optimal growth. Ideally this water will be applied incrementally rather than in one (potentially soil eroding) blast as in a 1” per hour thunder shower. With our limited irrigation capacity we struggle to keep our market garden adequately watered in a dry year. Such was the case this season, by mid-July we were in the throes of a mini-drought with prospects for a good 2nd cutting of hay beginning to appear dim, pastures looking scorched, and vegetable crops limping along with just barely enough soil moisture (except for our 1/2 acre of cucurbits and night-shades on plastic with drip who were loving all the heat and sunshine).

Cultivater setup with Lely weeder for blind cultivation – photo courtesy of Walt Bernard

Within the growth cycle of the potato the most critical point for insuring adequate watering is shortly after the plants flower because it is at this junction that they begin to put their energy into tuber development. This season we got lucky to catch just enough intermittent thunder showers to augment our overhead irrigation and deliver sufficient water to the spuds (unlike so many farmers who suffered under intense drought conditions). In other dry years we have brought in drip irrigation after the final cultivation. We do not have a line for every row, but instead manually lift the lines over one row to the next. The biggest factor affecting potato yields this year was higher than “normal” temperatures from the very start of the season and continuing on through the summer.

Potato Digger

An old tool that is still commonly used for digging potatoes on many contemporary small horse powered farms is a middle buster designed to be pulled by a team. Many farm museums have fine examples of such tools for digging spuds in which the double-sided share rides behind a set of depth gauge wheels and is trailed by long tines for catching the lifted spuds and depositing them on the surface free of dirt. These types of team implements for digging potatoes were the first big innovation in horse powered potato harvesting in the mid-19th century. Prior to the horse drawn digger the limitation on how many potatoes a farmer could plant was how many the farm crew could dig by hand. The basic design of these early diggers works so well that new models of this type of digger are once again being manufactured by contemporary horse drawn equipment suppliers. As discussed in Part One, besides the walk-behind version, the middle buster attachment is often seen nowadays on a tool-carrier cart designed to be pulled by two horses and to straddle the row.

The next big innovation in harvesting potatoes was the two-wheeled single-row potato digger. The Hoover digger was the prototype which featured a large forward digging blade affixed between two heavy cleated iron wheels with a driver’s seat mounted above the axle. The potatoes are lifted by the blade then move onto an elevator with a ground driven chain web consisting of straight steel bars linked together with gaps to allow soil, small, stones, and debris to be shaken out to fall back onto the field (larger stones usually slough off to the side or are carried over the elevator with the crop). The potatoes are then deposited in a narrow row behind the digger for easy hand picking. Ground driven potato diggers of this kind became very popular and were manufactured by the thousands. Issac Hoover was an Ohio farmer who specialized in potato production. He became one of the biggest producers of potatoes in his county but found the hand digging of spuds on a large scale was an obstacle to profitability. He also was a man with an inventive mind and figured there must be a way to harness the strength of his work horses to get the crop out of the ground. He developed his first prototype elevator digger in 1885. The digger was designed to be pulled by a team (for larger acreage or in heavy soils it was not uncommon to fold in a third horse) and could harvest upwards of 500 bushels per 8 acres in a single day. The utility of the machine was immediately appreciated by his neighbors and by the following year, along with his brother-in-law he established the Hoover & Prout Co. to manufacture and promote the new digger. By 1915 the company employed nearly 100 people and had a yearly output of 5,000 machines. At the dawn of the tractor age, Hoover came out with a digger with an engine mount to lighten the load of the horses. The company was bought out by the John Deere Company in 1926 (Deere had been the sole distributor of the digging machines since 1914), which commenced to manufacturing their own line of diggers based on the Hoover. These diggers featured a secondary attachment that separated the potatoes from the vines. Serviceable examples of these diggers are still in operation on many small farms across the country and can commonly be found for sale.

The ground driven single row potato digger held its own right up until the mid-20th century, after which time John Deere came out with a PTO (power-take-off) driven version. In subsequent years tractor-drawn and self-propelled spinner harvesters were developed that deposited clean potatoes onto a trailer or bagging platform. For smaller farms new lines of single row elevator-style potato diggers are still being manufactured and are sometimes used on horse powered farms but these run off the PTO and so require a motorized forecart to operate.

We paid $50.00 dollars for our Hoover single row potato digger and invested another $125.00 dollars in restoration (primarily to replace missing or decrepit lengths of drive chain). Like so many examples of vintage horse drawn equipment one is likely to encounter, our potato digger had been retrofitted to be pulled behind a tractor. Unfortunately, it was evident that the machine had continued to be used even after one of the ground drive chains had busted. This resulted in a torque being thrown into the entire frame and a cracked axle housing on the side without the drive chain. In spite of these deficiencies, with the help of our neighbor, Bud, we were able to rehabilitate the digger sufficiently enough to have it perform an admirable job of unearthing the spuds and leaving them on the surface in a neat line ready to be picked up. For us, who had been used to digging all of our potatoes out of the ground with spade forks, the performance of this near derelict antique felt like nothing short of a new agricultural revolution.

Bud lives across the street from the farm and, as a one-time farm kid and retired diesel mechanic who worked on agricultural machinery, he can’t help himself from having his morning walk include a glance over to see what his farming neighbors are up to. If I don’t have a restoration or repair job going on in the shop Bud leaves a little disappointed. He has helped us out of countless equipment jams and never wants anything for his time (though he will take a sack of sweet corn or 1/2 peck of potatoes when offered). The only pay required for Bud’s expert help on machinery is a willingness to listen to his stories as we work, and that is no cost for they are always instructive and entertaining. Like the one about the time his dad (who kept horses on the place long after all the neighbors around had sold them off for tractors) came up from the field with a team driving a wagon loaded with loose hay just as visitors pulled into the farm from town. Bud’s dad hopped off the wagon and went inside with the guests to have a cold drink and swap news. They were all seated in the parlor when the sky cracked lightning and rain came down. His father ran out to get the wagon into the barn only to find that the team and wagon were gone. The sliding doors of the big barn were shut. He looked everywhere for those horses except in that small barn down the lane that you have to back the load into because the approach was so steep and the clearance into the central alley was a matter of inches on either side (he had always been proud of his own skill at being able to back a team with a loaded wagon into that tight spot — nobody else on the farm even wanted to try it). Having exhausted all other options, he ran down the lane to the small barn and found the team and wagon backed safely into the barn waiting out the storm.

The elevator hitch on the forecart for pulling the potato digger.

After freeing up all the frozen parts and replacing broken and missing drive chains, the next challenge we faced with the digger was how to pull it. These diggers originally came equipped with a truck, which provided a stabilized hitch point for the team and also set the digger at the correct height from which to use the depth gauge lever at the front for transport mode and for setting the depth for the digger blade. We have a horse farmer friend who has a digger with the original truck. The truck is shaped like an hour glass of solid steel set on its side — this shape allows the truck wheel to roll over the rows of hilled potatoes with the least amount of resistance. It is a rare and lucky find to discover a digger that still has the truck attachment as most of these were sent to the scrap yard after the digger was adapted to be pulled behind a tractor. Having faced a similar dilemma with our horse drawn disc harrow, we decided to try the same solution of pulling the implement behind the forecart. The problem was the draw bar on our forecart is set too low to allow for transport of the digger, the blade would scratch into the ground. We decided to try and fabricate an elevated hitch above the existing one. When you’ve been on the same place for a while you tend to accumulate little stock piles of treasures, odd bits of equipment and pieces of scrap metal that you keep just because “they might come in handy someday”. And even though such stashes might look like junk to some, it is on such occasions as this that something you had no idea why you kept turns out to be just the thing you need.

The potato digger hitched to the forecart.

The elevated hitch we made is composed of a tractor draw bar (the kind that is used as a spacer on a three-point-hitch) two lengths of steel pipe cut to size (6”), two steel bolts to thread through the pipe to hold the draw bar in place, and a light gauge section of chain to anchor the draw bar to the cart (see accompanying photo). By using a clevis to hitch the digger to this elevated draw bar we could now safely transport the digger to the field. The height of the hitch was also perfect for setting the depth gage lever.

In order to use the potato digger we had to widen our row spacing from 32” to 36”. The reason for the wider row spacing is to accommodate the digger which has a 44” wheel base. If we went with our usual 32” spacing the flanged wheels of the digger would chop up the potatoes in the rows next to the one being dug. The potato digger works best in a loose friable soil (although it handles stony ground quite well). Prior to planting potatoes the ground should be worked deep to insure high yields. The point of the digger’s lifting blade will move through the ground with less draft resistance if you give it a little sharpening with a hand-held shop grinder. You don’t want to over-do this and create a knife-like edge, simply grind it down lightly to remove the bluntness that is the result of those many years of work the old digger has seen.

Before taking the digger out on the forecart with the horses we gave it a test run on the tractor. In this case to hitch up the digger, I used the same kind of draw bar on the three-point hitch as we used to make the elevated hitch on the cart. We did a test row and found the digger was working well enough but the potatoes were not coming out cleanly behind but were kind of buried again behind the digger, easier to find than digging by hand but not quite what we expected. But the test run did give us the confidence to feel we could safely try out the implement on the cart with the horses. Much to our surprise, the digger worked much better under live horse power; the potatoes were almost all left cleanly on the surface for easy pick-up. The difference was in the speed. When I went with the tractor (27.5 HP Kubota) I put it into low gear. The Fjord horses could not handle that pull in their version of “granny gear” they had to take it at a fast walk, but the machine worked much better at that speed (probably about 3 mph).

The wheels on the digger each have two keys that are turned to engage palls to set the wheels into gear. I found it helpful to have an assistant turn those keys for me rather than having to get on and off the cart. Once we started digging, we found it made sense to keep the wheels engaged until we were finished and only took them out of gear to transport the digger back to the equipment shed. The machine was originally set up with a seat on a cross brace positioned more or less over the axle. In the days before OSHA (Occupational Safety and Health Administration) standards were set, manufacturers created farm implements that had teamsters perched and balanced in a lot of unwieldy places and in close proximity to moving parts. I personally know teamsters of great skill and exceptional horses who still use these implements as designed, but for my part I was happy to be up on the seat of the forecart while the digger did its thing.

When I told a friend (who has farmed with horses his entire life) that I was using one of these diggers with our Fjord horses he cocked a skeptical eyebrow, and for good reason, as the potato digger is a hard pull. In most situations you will probably require a heavy team of horses or three draft ponies to handle it. We can get away with it here because we have such a light sandy loam. Even so, by the time they reach the end of a row the Fjords dig in like pulling ponies at the county fair to make that machine work. My neighbor Bud was impressed enough to remark that, “those little horses showed me something”. Also, we came up with a strategy of only digging four 180’ rows at a time. This made sense for several reasons. Firstly, in order to dig consecutive rows you have to have enough farm workers picking up potatoes behind the digger to clear the way, otherwise when you move from one row to the next the flanged wheels of the digger will chop up some of the unearthed potatoes. Secondly, digging every other row and just four rows at a time was “do-able” for our little team (approximately 14 hands and 900 lbs.) and didn’t sour them on the machine. Thirdly, even with the digger unearthing them, it still takes one person about 20-30 minutes to gather up a 180’ row into crates, so four rows was about sufficient to occupy our labor force on a busy harvest day while leaving time to get to harvesting other crops for our CSA. We wound up bringing the digger out on four separate occasions to dig four rows at a time and had all the potatoes out of the ground by the first week in September (the first row of early red Norlands was dug by hand as was the last row of purple Peruvians — the majority of our crop consisted of the waxy yellow Carola and the standard white Kennebec).

We used to face the immensity of digging potatoes by hand by doing so in increments. Soon after the 4th of July we would begin digging new red potatoes for our CSA members and other markets. From that point on potatoes would be dug every week as part of the regular harvest. Even so, we would always wind up with several rows waiting to be dug all at once at the end of the season. What was worse, after the vines died back the weeds would take over and the remaining spuds would be lost in a jungle of pigweed and lambsquarters. More than once I had to resort to bush hogging the weeds down before we could get in and dig. On the other hand, neither did we have refrigeration so it seemed that until there was danger of the ground freezing the potatoes would keep in the ground as well as anywhere (except in one exceptionally droughty year in which the tubers began to dehydrate in the soil and had to be dug right away). A couple of years ago we invested in a CoolBot refrigeration unit (1) and installed it in an insulated walk-in cooler room built in the barn. The CoolBot is a patented invention that adapts a standard air-conditioner to function as a refrigerator compressor. We are now able to keep produce stored at between 40-44 degrees year round. This enabled us to dig the potatoes when they were ready (once the skins are no longer slipping) rather than waiting till the weather turned cool enough to allow us to keep them in a root cellar.

No doubt we will continue to experiment and fine tune our potato production, but we felt gratified this year in making several adaptions that allowed us to replace human-intensive power with live horse power. In fact, by furrowing, harrowing, cultivating, hilling, and digging our potatoes with horse drawn implements the only hand work involved was in setting the seed with students and in picking up the dug spuds at harvest. Such small successes in the farming life can tap into sources of deep joy drawn up from roots in the soul of the farmer and lead us to dream of other possibilities…