Food Webs on Farms and Gardens

Image shows cattle and chickens foraging in a mixed species pasture. Orchard saplings grow in the same cover crop mix nearby. A closeup image of the cover crop is also shown. Farms and gardens that maintain active food webs produce healthier food. 

When soil contains sufficiently diverse and abundant live microorganisms, food webs develop.  These food webs release nutrients from deep within the soil profile, and deliver them to plants in eco-friendly, bioavailable forms.  The result includes well-nourished plants that are better able to protect themselves from pests and disease.

This means crops and livestock grown in the presence of healthy food webs are less likely to require costly chemical inputs. The result is win-win for farmers and for consumers of farm products.

How much diversity is enough?

One reason many farmers and gardeners rely on chemical approaches is that chemicals come with standardized recommendations.  A grower can be reasonably certain that when they use a chemical according to the label, their pests will be controlled.

Using biological methods that result in healthy food webs requires more thought on the grower’s part.  Careful observation, trials, and errors are all part of learning to work with food webs. The good news is that farmers and gardeners who choose this path and stick with it are usually pleased with the results.  This is because productivity, food quality, and even profitability can increase as food webs grow and develop.

The model below illustrates the strategy we are using to add biodiversity to our demonstration farm.

Building food webs on 7 acres.

Farm management decisions are based on the general premise that more species are better–up until the point when management demands become too high.   Three fenced pastures allowed the farm to be divided into one large section for an orchard, and two smaller pastures for feeding livestock.

Before planting, the soil was tested.  Results indicated the soil was low in micronutrients, microbial communities were poorly developed, and organic matter fell below the 3% threshold important for carbon management.   Weeds were prevalant.

To build organic matter, feed soil microbes, and create habitat for microorganisms and macroorganisms, an 18-species cover crop was seeded in all three sections.   The cover crop will also reduce opportunities for weeds to establish, and will provide rich forage for livestock.

Once the cover crop established, an orchard was planted with bareroot trees.  These included 7 apple varieties, pears, cherries,  and 3 peach varieties, 2 pear varieties, and one bing cherry variety.

Free range chickens are allowed to forage in the orchard and both pastures, providing fresh eggs.  The chickens also keep flies and other pests under control.  Feeder steers are rotated through the two grazing pastures, allowing forage in one pasture to recover while the other one is being grazed.  Foraging activity, properly managed, will increase the rate of soil improvement by adding manure and accelerating plant growth.

Indicators of adequate biodiversity

Monitoring trends is essential to determine whether the diversity of plants and animals is sufficient to promote healthy food webs.  The following parameters are routinely monitored:

-Soil organic matter.  The goal is to reach 5%, then re-evaluate.

-Microbial density and diversity.  The goal is to increase overall abundance and increase fungal dominance.

-Nutrient levels, including micronutrients. The goal is to achieve optimal levels of nutrients within plant tissues.

-Soil pH.  The goal is to reduce pH to neutral levels.

-Pest counts.  The goal is to maintain minimal pest levels and pest damage across seasons.

-Soil, crop, and livestock health.  Qualitative assessments are performed daily through field observations.  When symptoms emerge, more quantitative diagnostics may be used.

-Profit and Loss statements.   While a young orchard will take years to turn profits, expenses must be closely monitored.

More about the farm

The farm described here is the newest addition to End-O-Fite Enterprises LLC.  The farm complements our mission by helping us provide nutrient dense food to our community.   The experiences we gain as we restore this land and deal with production challenges will enhance our ability to provide workshops and virtual training.

Newsletter subscribers will receive updates to show how we adapt and evolve as our orchard matures.

 

 

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