Optimal Nutritive Value of Honeylocust Seed Pods Within Temperate Silvopasture

Optimal Nutritive Value of Honeylocust Seed Pods Within Temperate Silvopasture

Summary

Nutritional analysis indicates Millwood seedpods have high digestibility, low fiber and relatively high seed protein concentrations. Nutritive value declines appreciably after pod drop if conditions are wet, but Millwood pods are more resistant to degradation than wildtype honeylocust pods. Whole seeds are largely resistant to short-term in vitro digestibility; however, ground honeylocust seeds are highly digestible. Thus, silvopasture systems utilizing honeylocust trees likely would best be deployed with ruminants that have upper dentition. Juvenile (13- to 15-yr-old) Millwood trees can produce sufficient seedpod yields to provide financial benefit for land managers.

Objectives/Performance Targets

The project had four main objectives:
1) Estimate the nutritional variability of seedpods produced from Millwood honeylocust trees managed in a silvopasture.
2) Determine yields and year-to-year variation of Millwood honeylocust seedpod production for trees managed within active silvopastures
3) Determine changes in nutritive value, digestibility, and mineral concentrations over time after seedpod drop in pods and seeds from two distinct honeylocust tree types.
4) Characterize changes in seedpod development and nutritive value through the growing season and to determine their relationship to time of seedpod drop.

Objective 4 could not be completed, however. Millwood trees did not yield enough seedpods in 2009 to conduct all proposed studies. Thus the pod development study was not conducted.

Accomplishments/Milestones

Original analyses for seedpod yield and nutritive value have been completed. Additional analysis looking at levels of pectin in seedpods is planned, however, as it appears that pectin caused some difficulty with traditional fiber analysis and delayed our progress.

The MS thesis defense is planned for early February, and we look forward to publishing our data soon after.

Impacts and Contributions/Outcomes

Our data suggest ground seedpods have similar nutritional profile to that of whole ear corn (corn + cobs). Based on our production data and on estimates of the value of oats – frequently cited in old literature – juvenile trees could produce about $150/acre worth of supplemental feed for livestock – particularly small ruminants.

Information on our research has found its way to Georgia and South Africa. We may help with nutritional analysis of seedpods used for wildlife plantings in Georgia. A producer in South Africa has asked us to ship Millwood honeylocust trees that are to be integrated into their goat production systems.

Collaborators: