A Comparison of Weed Control Strategies in Christmas Tree Plantations Using Mechanical and Chemical Methods or Shropshire Sheep

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Commodities

• Agronomic: clovers, grass (misc. perennial)
• Additional Plants: trees
• Animals: sheep

Practices

• Animal Production: grazing - rotational, stocking rate
• Crop Production: silvopasture
• Pest Management: Weed Management
• Production Systems: integrated crop and livestock systems

We focus on the production of sheep and Christmas trees. We can
produce quality products, but our resources also can be limited
in achieving these goals. One restraint is labor. Both Elise and
Jeff are employed off-farm, which can sometimes conflict with
farm needs. We are located in a rural area with a limited labor
pool, and we are not yet profitable enough to pay staff anyway.
Land also is limited. Our 12 acres are landlocked. While we may
obtain space to expand in the future, we currently must use all
resources in the most efficient way possible. Because of these
restraints of time, labor, and space, we are looking to combine
the processes of raising sheep and trees as much as possible to
the benefit of both commodities.

Solution: 

As a solution to our limited time, labor, and land, we will
combine elements of our sheep and Christmas tree operations and
examine how they can each benefit the other. We propose
introducing sheep into the Christmas tree stand to eat weeds.

Within Christmas tree plantations, weed control is an ongoing
challenge throughout the growing season. Dense, tall vegetation
can stunt, if not kill, the trees by robbing nutrients and
moisture that the trees need. However, this vegetation is an
unused resource that could be used to feed our sheep. Grazing the
sheep within the trees will potentially reduce the time, labor,
and land we need to control the weeds and feed our animals. Our
research trial will examine the labor and material costs of sheep
grazing versus the labor and material costs of mechanical and
chemical weed control in a Christmas tree plantation.

Sheep can provide fertilizer, as well, and potentially reduce the
labor and costs of mechanically and chemically controlling weeds.
The symbiotic relationship saves on sourcing other forage and
minimizes, if not eliminates, chemical and mechanical weed
removal.

For our trial, we will designate two areas in our acre of 800
second-year trees. In our control area, we will manage weeds
conventionally by mechanically mowing, spraying herbicide, and
spreading mulch or compost around the base of the trees. In our
experimental area, Shropshire sheep will graze amongst the trees
in a rotational grazing system.

Our methods will measure the amount of time that we spend with
each weed control method. For conventional weed control, we will
measure the amount of time used to mow, apply chemicals, and
mulch the trees. We will also analyze the cost of materials for
mechanical and chemical methods.

For sheep grazing, we will analyze the cost of materials and
measure how much time is used to set up the sheep paddocks using
solar-powered temporary netting, move the sheep, and provide
daily care and feeding. While we are using Shropshire sheep,
which have a good reputation for working among tree plantations,
the sheep will need to be moved as soon as they have exhausted
their forage to eliminate the possibility of damage to the trees.
To do this, we will need to monitor the sheep through webcams.

The following materials are needed:

For the sheep grazing area:

1. Shropshire sheep
2. Netting
3. Solar charger
4. Trail cam
5. Water wagon and tanks
6. Supplemental feed
7. Feed/mineral feeders
8. Shade
9. Fly control

For the chemical and mechanical control:

1. Herbicide
2. Chemical sprayer
3. Mulch or compost
4. Mower

The sustainable agriculture practices we will be using include
rotational grazing and intercropping.

Objectives: 

Our objectives center on discovering what symbiotic relationship
can exist between sheep and Christmas trees and sharing the
results of our research trials with other Christmas tree growers
who will benefit.

• Determine how many days sheep can graze within a Christmas
  tree plantation without disturbing the trees
• Evaluate two systems of weed control in Christmas trees
• Share findings through conference presentations