Research Report: Improving Cool-Season Pastures with Interseeding Annuals and Grazing, Update 2016
For the last three years, PFI farmer and avid on-farm researcher Bruce Carney has experimented with interseeding diverse mixes of warm and cool-season forages into his perennial pastures. Bruce’s goal is twofold: to provide abundant, nutritious forage to his grass-fed beef herd year round, and to continually improve the health of his soil. In the summer of 2015, a field interseeded with soybeans, German millet, pearl millet, buckwheat, forage radish, turnips, and kale yielded 4.3 DM/tons/acre in mid-August, which Bruce baled and fed during the winter. The baleage was fed in the same field it was harvested from, to return fertility to the soil.
Project Objective: To experiment with seeding multi-species forages into existing pastures and monitor performance of livestock, forage and the soil.
In a Nutshell
- Interseeding annuals into pastures increases forage diversity, quality, and quantity.
- Bruce Carney developed seed mixtures and interseeded them into existing cool season pastures.
- Seed mixtures vastly increased pasture diversity.
- Grazing management to harvest or trample forage at the right time and to a proper degree is essential to feed both livestock and soil microbes.
- During the establishment year in 2014, few advantages were seen in grazing days or forage yield, but a baseline was established for future comparison.
- In 2015, two fields were seeded once with a cool season mix, and one field was seeded multiple times with cool and warm season mixes.
- Total tons of dry matter harvested by cattle or baled was greater in 2015 than 2014; animal unit days provided from forage produced were doubled from year 2014 to year 2015.
- After multiple interseedings and two years of rotational grazing on three pastures, compaction near the soil surface (<6 inches) increased but decreased deeper down (>21 inches).
In total, Bruce received 528.6 animal unit days (AUD)/acre from the pastures in the study, compared to 264.6 AUD/ac in 2014. Not only did forage quantity increase, but “The forage mixes I had in the pastures were higher quality for finishing grass-fed beef, which raised the total quality of my pasture, resulting in more pounds of beef produced than if I just had perennial pastures,” added Bruce.
For more detailed results and discussion, view or download the full research report on the PFI website.