Cultivating Questions: Preparing the Orchard Site
by Anne & Eric Nordell of Trout Run, PA
In the spring of 1997, we plowed up a narrow contour strip wrapping around the south side of the market garden with the idea of eventually expanding production. Since the east end of this field seemed too steep and stony for vegetables, we decided that this site would be more suitable for a small orchard. Although we had no experience managing fruit trees, we were inspired to plant enough apples to meet our own needs after seeing Soil Conservation photos from the 1930’s which indicated a well established orchard on this same sidehill site.
We thought this southeasterly slope might be ideal because it receives some buffering from the prevailing west winds as well as plenty of early morning sun to dry off the foliage. We also expected that this location, right below the vegetable fields at the crest of the hill, would provide the best frost drainage on the farm. Most importantly, the young trees would be protected from deer by the seven wire sloped fence described in the Spring ‘97 SFJ.
Like the rest of the farm, this long neglected hay field tested low in fertility and was completely infested with quackgrass. Quack grass is a pernicious weed in our area because of its rhizomatous root system. If you chop up the rhizomes in an effort to set back the quack, you end up multiplying the plants.
We turned to a traditional farm practice called The Summer Fallow to clean up the quack grass. Anne learned this technique while in partnership on a large herb farm in Washington where they used a ten foot chisel plow to work up forty acre fields of quack-infested sod before planting the medicinals. Large sweeps mounted on the chisel plow shanks undercut the grass and lifted the rhizomes to the surface. At the same time, a flexible pasture harrow attached to the back of the chisel plow rolled the roots over, shaking the dirt off the rhizomes and exposing them to the drying effects of the sun.
The usual practice at the farm in Washington was to work the ground with this rig every few weeks throughout the summer to dehydrate the rhizomes. Then, in the fall, they planted the field to a thick stand of rye in order to smother out any quack grass which had survived the summer fallow.
The following year the rye again competed with any lingering quack by sucking the ground dry before the grass had the chance to start growing. After rye harvest, they put the fallow field into clover for a year or two to boost the soil’s fertility before planting the first crop of perennial herbs.
This photo essay tries to show how we adapted this weed control strategy to our tools and our site while preparing the land for the new apple orchard. We used this same combination of the summer fallow and cover crops during the first years on the farm to clean up the quack grass and build up the soil before planting the six acres slated for vegetable production. For more background and details, see “The Summer Fallow” in the summer 1991 issue of Small Farmer’s Journal.
Skim Plowing the Old Sod
We turned under the old sod in the contour strip in the spring of 1997, adjusting the old Leroy walking plow to cut as shallow a furrow as possible. We had already learned by trial and error that plowing 2-3″ deep is a much more efficient and effective way to work up the sod than trying to chisel a tough old hay field with a team of two horses. Either way, the idea is to undercut the root system of the quack grass as shallowly as possible in order to keep the rhizomes close to the surface.
For some pointers and history on this skim plowing technique, please see “A Few Long Furrows” in the Spring 1993 SFJ. (This article is also included in the booklet mentioned near the end of the Cultivating Questions column.) In a nutshell, skim plowing is just a matter of lowering the depth wheel and the angle of the plow clevis. Hooking the horses’ traces shorter may also be necessary to lift the beam of the plow so the share rides only a few inches deep in the soil. We also recommend using a good share and landside to maintain suction and balance when plowing so close to the surface.)
The big advantage to skim plowing the quack infested sod was then we could rip up the root system and lift the rhizomes to the surface with a horsedrawn harrow working just the top few inches of the soil. The springtooth harrow also brought a lot of sod clumps back on the surface to speed up decomposition and help hold the soil during heavy rains.
We harrowed the contour strip every two-to-three weeks to dry out the roots and prevent the quack grass from greening up. In this way, rain or shine, we could starve out the quack grass by draining the energy reserves of the rhizomes.
(A point of honesty: Unfortunately, we did not document the initial tillage of the contour strip so we have substituted with these two old photos of skim plowing and harrowing a well-sodded cover crop of rye in the market garden. The techniques are the same although the old grass sod plowed up a lot rougher. In fact, we found it advantageous to use a disc the first time over the skim plowed sod furrows and to give the grass plenty of time to rot down before ripping deeply with the spring tooth harrow.)
Dehydrating the Rhizomes
After the sod was well broken we found this riding cultivator equipped with wide sweeps and a small section of flexible pasture harrow to be more effective at drying out the quack than the spring tooth harrow. Mimicking the chisel plow setup used in Washington, the sweeps on the horsedrawn cultivator undercut the weeds and lifted the rhizomes to the surface where the pasture harrow, dragging behind, loosened the soil and exposed the roots to the sun.
We clamped the shanks eight inches apart on the gangs of the cultivator so that the 12″ sweeps overlapped each other by at least two inches. In this flying geese configuration it is almost impossible for the weeds or roots to slip by the sweeps.
This is the same cultivator setup we use for forming the planting beds in the market garden. For details on how the middle sweep is attached to the gangs, and removed for row crop cultivation, check out the video or the article “Trashed Out Onions” in the Summer ‘94 SFJ or the booklet.
Suppressing the Weeds with Rye and Lime
At the end of the summer we seeded the contour strip down to a thick stand of rye. This winter hardy cover crop really took off just as the growth of the grasses and weeds naturally slowed down. We have found that a well-timed “smother” crop like this rye is far more effective at setting back the weeds than working the ground with the cultivator during the cool, moist conditions of fall.
After the rye cover crop was well established, we had lime applied to the contour strip at the rate of 2 tons/acre. We had learned during the first years on the farm that raising the pH and calcium levels of these long neglected soils with high calcium lime shifted the growing conditions from favoring the grasses to favoring cultivated crops like the vegetables grown in the market garden.
(For more details and opinions on lime’s important role in building up soil structure, increasing insect resistance and reducing weed pressure, see “The Calcium Controversy” in the Spring 2001 SFJ column.)
Cover Cropping for Soil Quality
We devoted 1998 to improving soil quality through cover cropping. Mowing the overwintering cover crop of rye in the contour strip several times in the spring seemed like the easiest way to generate a lot of free organic matter with the team while reducing the bulk of the rye biomass into a management mulch for horsedrawn plowing.
The trick was to clip the rye before it elongated a seedhead, in this way encouraging it to tiller and regrow after each cutting. The substitute photo shows the second mowing at the beginning of June with a good bit of plowable organic matter already accumulated right in the field.
We plowed down the rye after the third clipping toward the end of June. As this seemed like a good opportunity to mix together the newly generated organic matter with the stratified layers of old fertility and acidity, we raised the depth wheel on the plow so the share would suck in more deeply than skim plowing the first fallow year. Deep plowing at the official start of summer also timed the decomposition of the cover crop with the most biologically active season of the whole soil profile.
Note the crumbly condition of the cover cropped soil despite plowing in wet conditions. This might seem far-fetched, but we think there is a connection between improving soil structure with the cover crops and reducing weed pressure. At least, we have often noticed that weeds seem to be worse where the soil is crusted or compacted. It is almost as if nature sends in the weeds to repair the damage done to the soil structure. We figured that if we could use the cover crops to perform this same role, then weeds would have less reason to grow.
Depleting the Weed Seed Bank
We settled the deep plowed furrows in the contour strip with this light disc, following immediately with the springtooth harrow and the cultipacker to smooth out the soil. Instead of leaving the ground in the rough like we did the first fallow year to dry out the quackgrass, this time we wanted to create a firm, moist seedbed to intentionally germinate a generation or two of annual broadleaf weeds, like lambsquarter or pigweed.
Each time a new batch of weeds germinated, we harrowed the field to nip them in their infancy, and then rolled the field to resettle the seedbed and germinate another generation of weed seeds. By performing this “stale seedbed” technique for six weeks during the peak of the growing season, we eliminated a lot of heat loving weeds from the seed bank a full year before planting.
We shifted our focus back to soil building early in August, seeding the contour strip to the second cover crop of the year. This time we mixed in some hairy vetch with the rye seed to fix some free nitrogen and add more diversity to the soil quality campaign.
The timing of this overwintering mix also took into account weed management, in that any remaining annual weeds which germinated with the cover crop frost-killed before setting viable seed like the dead pigweed you see in this photo. Planting the rye and vetch at this unusually early planting date maximized the soil structuring potential of the cover crop without compromising weed control.
Before skim plowing the rye/vetch sod in the Spring of 1999, we applied hog composted horse manure at the rate of 10 tons/acre. We planted the west end of the contour strip to a mix of LATE planted vegetables, beginning with squash and zucchini in early June and ending with fall crops of napa and kale in July. We cultivated the crops a few times, but thanks to the weed management during the preceding two fallow years, we never had to hand hoe the rows. Despite the dry, hot conditions we faced that year, these crops produced exceptionally well.
Mulching the Young Trees with Homegrown Clover
On the stonier and steeper east end of the contour strip, we planted 18 two-year-old whips. As we did not know the first thing about orchard culture, we followed the planting and pruning suggestions found in Michael Phillips’ The Apple Grower. Once the apples seemed well established, we seeded down the contour strip on either side of the tree row to a mix of covers and grasses.
This photo shows the east end of the contour strip nearly a year later on the 8th of July, the year 2000. A couple of weeks earlier we had mowed two rounds of the 4-5″ tall clover on each side of the tree row and raked the residues around the base of the trunks to serve as a moisture-conserving, weed-suppressing, fertility-building mulch.
Without a doubt, preparing the site is the easy part of apple management, especially compared to controlling insects and diseases in the established orchard. The most we can say at this early date is that a couple of years of rotational cover cropping and tillage with the team got both the young trees, and their perennial source of mulch, off to a good start.