Determining the Effect of Tree Pruning and Nutritional Inputs on a Neglected Chestnut Orchard

Progress report for FNE22-007

Project Type: Farmer
Funds awarded in 2022: $29,975.00
Projected End Date: 02/28/2025
Grant Recipient: Morris Orchard LLC
Region: Northeast
State: Maryland
Project Leader:
Jane Dennison, Ph.D.
Morris Orchard LLC
Expand All

Project Information

Project Objectives:

This SARE project will quantify changes in production and soil health as a function of pruning and nutritional inputs over three years. Based on the data, we will estimate the potential increase in income with continued treatment and compare with the expenses. This may provide some information on the viability of restoring mature chestnut trees through pruning and nutrition.


  • To determine the effect on yield of pruning a neglected chestnut orchard
  • To determine the effect of nutrient applications on soil health.
  • To gather data on whether pruning and adding nutrition is cost effective for a neglected orchard

Tree crops like chestnuts take considerable investment of time and money to established before producing a yield that can generate income for the farmer. Chestnuts begin producing 7-8 years after planting seedlings and should begin to show profit around year 10. Neglected orchards of chestnuts and other tree crops exist in our region that have the potential to be profitable farming enterprises. Demonstrating that intensive pruning and nutrition increase yields to profitability, accompanied by outreach to orchard owners, will encourage orchard restoration.

Pruning removes dead and diseased wood, increases light and airflow and results in increased productivity. However, pruning large mature trees requires specialized equipment and skilled labor and is a costly endeavor. Farmers seek return on investment for such a large expense.

Good nutrition is also important for orchard trees, increasing their resistance to pests and disease and giving them additional energy for crop production. Ramial wood chips have been shown to increase yield and water retention when applied to agricultural soils. In addition, ramial wood chips feed the fungal components of soil which create symbiotic relationships with tree crops. Ramial wood chips are commonly available from arborists in most areas making them an accessible and affordable soil amendment. Enhancing mineral concentrations available to the trees will also increase their productivity and resistance to disease and pests. Finally, we include in this proposal the application of liquid nutrition such as compost tea but are waiting for preliminary test results before selecting what to apply.

We will estimate the expense and increased production on pruning mature chestnut trees and providing additional nutrition to shed some light on whether it is economically viable to restore a neglected orchardThese restored orchards can produce crops sooner and in larger quantities than newly planted orchards. They can be profitable businesses for farmers and employ workers in farm communities to prune trees and harvest crops. Demonstrating that unmaintained mature orchards can be profitably brought back into production may also protect mature orchards from being destroyed and save important varieties and genetics.


Click linked name(s) to expand/collapse or show everyone's info
  • Michael Judd - Technical Advisor
  • Taylor Logsdon


Materials and methods:

Defining the test groups:

A section of the orchard's chestnut trees have been divided into four groups of 14 trees each (the whole orchard was not selected for this study due to the high costs of the arborist.) The groups were selected based on similar tree density and site conditions (see attached orchard schematic). Each group will be marked in the orchard using color coded flags. The groups will be assigned treatments: Group 1: pruning only, Group 2: nutrient application, Group 3: pruning and nutrient application, and Group 4: control, no treatment.

Treating test groups:

Trees in Group 1 and Group 3 will be pruned each winter for three winters. No more than 25% of the tree will be removed each year to ensure the health of the tree. The farmer will consult with the technical advisor and arborist as to the best approach to pruning the trees.

Trees in Group 2 and Group 3 will receive nutrient applications:

  1. Wood chips will be delivered by tree service companies and amassed on site. They will be kept in open piles not to exceed 20 yards each. Once 56 yards of wood chips are collected they will be spread through the orchard at a rate of 2 yards per tree in July 2022 and July 2023. Wood chips will be spread under the canopy of the tree but not on the orchard ground between trees. A tractor front loader sized to deliver the correct amount of wood chips for each tree will be used for spreading.
  2. Minerals: The local chapter of the Bionutrient Food Association is headed by Richard Jeffries who has advised us on mineral application. We will use rock dust from a local quarry but are not including this as a cost on this proposal since we will be getting a bulk supply for use on this orchard and elsewhere.
  3. Liquid compost soil drench: We are taking a preliminary soil sample in November 2021 for laboratory analysis and will consult with the laboratory and Dr. Elaine Ingham’s SoilFoodWeb School ( for the best product to apply. Our technical advisor, SilvoCulture, Inc., will pay for this preliminary expense. We will also refer to the Rodale Institute guide on compost teas (

Soil Health Analysis:

Based on recommendations from the Bionutrient Food Association, soil health will be measured using Earthfort Lab’s #2 package which tests for total/active bacteria, total/active fungi and protozoa, pH and #7 package which tests for pH, calcium (Ca), % humus, soluble salts, nitrates (NO3), ammonium (NH4), phosphate (HPO4), potassium (K), magnesium (Mg), iron (Fe), manganese (Mn), boron (B), copper (Cu), zinc (Zn), sulfates (SO4), clorides (Cl). A composite sample will be taken from at least 8 locations within each test Group for a total of 4 samples per year to be sent for analysis

Background soil testing will occur in April of 2022 to establish existing soil health conditions of the site. Additional testing in April 2023 and April 2024 will be used to determine the effect of nutrient application on soil health.

Determining Chestnut Yields:

Each October during the grant period chestnuts will be gathered with the help of volunteers from all the tree groups for the duration of the harvest. Volunteers will be recruited through SilvoCulture’s email list. This has been successful for harvesting chestnuts from the orchard in 2020 and 2021.

Gatherers will be assigned rows to walk and methodically collect all fallen chestnuts from each tree in a group. Chestnuts will be collected into 5 gallon buckets marked with the color code for the tree group. Chestnuts will be kept separate per the test Group and sorted based on condition. Nuts will be sorted by the following criteria:

 1) Marketable nuts as a raw product: must be free of disease and blemishes.

 2) Seconds suitable for processing into value added chestnut products such as flour or beer but not suitable for direct sale: May have small blemishes both on shell of nut and interior but must otherwise be in good condition.

 3) Nuts not suitable for direct sale or value added products: Are diseased or damaged to the point that they are unmarketable and not suited for creating value added products.

Nuts will be collected every other day to reduce loss from wildlife and weevils. All nuts will be given a hot bath at 120 degrees Fahrenheit for 20 mins to kill any weevil eggs present. This will be done using our SilvoCulture’s “Chestnut Dunker” which has been used successfully in 2020 and 2021 on chestnuts from the orchard. The dunker consists of a tank of water kept at a steady temperature of 120 degrees by a digital thermometer and propane heater.

The following data will be recorded:

-Yield of chestnuts from each tree group per season

-Cost of materials and labor for work done on each tree group

-Revenue of chestnuts based on price attained through local sales

We will analyze the data looking for statistical differences between nut yield/quality and soil health for the 4 test groups and the effects of yield on pruning and amending with wood chips a neglected chestnut orchard. Revenue from the chestnuts will be quantified through prices obtained from local sales and compared to the cost of work done on the orchard. Local sales will be made through SilvoCulture’s chestnut roast festival and our social network. Value added producers of bread and beer will be identified as buyers for quality chestnuts.


Activities Completed in 2022

Defining the test groups: Test groups were marked with different color marking flags to identify which trees belonged to which group. A change in treatment to groups was decided upon to allow for easier spreading of wood chips. Group 1 (Yellow) was pruned and fertilized, Group 2 (Green) was fertilized and not pruned, Group 3 (Blue) was not fertilized and not pruned and Group 4 (Red) was pruned and not fertilized.

First pruning of chestnut trees:

Trees in Test Groups 1 and 3 were pruned in March of 2022. Technical Advisor, Michael Judd met with an arborist on site and determined the best approach to pruning the trees over the three year grant period. The amount pruned from each tree varied depending on the amount of disease and dead wood in each tree. Photos for each of the trees in the grant were taken as a record of the pruning done to them. The second pruning of the trees will occur this February 2023 and will focus on shaping and training the new growth of the trees.

Soil Testing:

Background soil testing was taken for each of the test groups and submitted to EarthFort Lab for analysis. In addition to receiving soil tests results support staff met with EarthFort consultants for a review of the results.

Chestnut Harvest:

Chestnuts were harvested by support staff and volunteers and careful records were kept of yield and quality of chestnuts for each test group. 5 gallon color coded buckets were used to keep nuts from each test group separate.

Soil Amendments:

Throughout the 2022 summer, wood chips were collected on site from local arborists and kept in piles to begin composting. Soil amendments were applied in fall of 2022 after the chestnut harvest. Head of the local chapter of the Bionutrient Food Association- Richard Jeffries, advised Morris Orchard on how to apply compost extract and rock minerals to the test groups . Richard also provided the compost and rock minerals. Compost extract was applied using a backpack sprayer, rock minerals were broadcast by hand and wood chips were spread using a skid steer.

Support staff applied the following rates of amendments to each tree in each test group:

  • 1 gallon of compost extract
  • 1.5 yards of wood chips
  • 1 quart rock minerals

Though an amount of 5 gallons of compost extract per tree was advised, support staff were only able to apply a gallon of compost extract in the allocated time. Morris Orchard is looking into a more efficient was of apply the extract for next season.

Only 1.5 yards of wood chips were applied instead of the planned 2 yards due to being unable to solicit the total amount needed from local arborists.


Research results and discussion:

Initial soil tests from 2022 have revealed that the current state of soil health and fertility in the orchard is in poor condition for growing chestnuts.

The following was found:

  • Total and active fungi is very low
  • Total and active bacteria is low
  • Fungi to bacterial ratio is too low in fungi for trees
  • Low organic matter at 4.5%
  • Low in most bio available nutrients

Yield data from the 2022 harvest:

Test Group Total Yield (lbs) lbs marketable % marketable lbs seconds % seconds lbs unmarketable % unmarketable Average Size
1 (Yellow) 44.1 24.3 55% 6.3 14% 13.5 31% medium/large
2 (Green) 172.9 68.5 40% 58.4 34% 46 27% small
3 (Blue) 127 54.7 43% 25 20% 47.3 37% small/medium
4 (Red) 136.4 54.3 40% 39 29% 43.1 31% medium
Participation Summary

Education & Outreach Activities and Participation Summary

10 Workshop field days

Participation Summary:

8 Farmers participated
Education/outreach description:


Fall Harvest 2022 (Workshop/ Field Days):

SilvoCulture staff reached out via Facebook and through our distribution list of 964 people to publicize the harvest event: we received 68 emails from people interested in volunteering, of which 20 showed up. The harvest was held from  9/20 to 10/12/22. Each of the four research quadrants were given a color and buckets marked with that color were used for the harvest and records were kept of the yields. Volunteers also helped with post-harvest activities including dunking the nuts in the hot water heater and sorting the nuts to remove bad ones. The volunteers consisted of people from diverse backgrounds interested in chestnuts for a variety of reasons. Of these, the most common were farmers interested in chestnuts as an agricultural crop and European and Asian immigrants with a fondness of chestnuts from childhood.

Workshop field days: 10

Farmers participating: 8


Introduction to SARE grant social media video:

Footage was taken of the 2022 pruning, soil sampling and soil amendments to be used in an introductory video of the SARE Grant to be shared via social media. The footage has been sent to a designer and is currently being worked on. We anticipate the video to be ready for release by spring 2023.

Workshop: "Pruning to Restore Orchards"

Our pruning workshop is scheduled for March 5th, 2023 and will include a demonstration of pruning by the arborist who has been pruning the orchard. Michael Judd will give a talk on the purpose of pruning the orchard and pruning considerations and decision making.

Learning Outcomes

8 Farmers reported changes in knowledge, attitudes, skills and/or awareness as a result of their participation
Key areas in which farmers reported changes in knowledge, attitude, skills and/or awareness:

The farmers that attended our volunteer chestnut harvest days reported a better understanding of the chestnut harvesting process, including:

  • the need to harvest frequently and continuously throughout the harvest period
  • the use of a hot water bath to kill weevil eggs within the chestnuts
  • the weevil life cycle and effect on nuts
  • the competition from deer and rodents
  • how to identify a good nut from a bad nut
  • labor and time required to harvest nuts


Project Outcomes

Assessment of Project Approach and Areas of Further Study:

Heavily pruned chestnut trees vs lightly pruned chestnut trees:

Upon inspecting the chestnut trees to be pruned within the grant the technical advisor and arborist decided that the best approach for some of the trees was to prune them back to the main limbs or trunks to take off all diseased wood. Of the pruned groups- Group 1 had 7 of the 14 trees main limbs removed and Group 4 had 4 of the 14 trees main limbs removed. The resulting new shoots will be thinned this and next winter to create new limbs for the trees. Though this may prove to be the most beneficial for the trees, it does pose a challenge for the yield data of the grant as these heavily pruned trees likely won't begin producing nuts before the completion of the grant. One possible solution to this is to remove the heavily pruned trees from the data set and find the average yield of the lightly pruned trees versus the unpruned trees.

Keeping "unmarketable" nuts data:

As part of the yield data for the grant, bad or "unmarketable" nuts were collected and kept separate from "marketable" nuts and "seconds". This data, though valuable, has made for inefficient harvesting of the nuts and a larger burden of time and labor for the supporting staff. Volunteers in the 2022 season picked all nuts from the ground including the bad nuts and these nuts had to later be sorted through and weighed by SilvoCulture support staff, a process that has turned out to be very time consuming.

Pest pressure:

Large deer and rodent pressure this year meant that many of the nuts that dropped were eaten. Support staff estimate that around half of the nuts were lost this way. Morris Orchard LLC will allow for hunting on the property in 2023 to help deter the deer.

With these considerations in mind, we expect that soil health data may be a better indicator of our efforts over the course of the grant. Chestnut yields may not be a good indicator during the course of the grant.

Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.