A Look at Pea and Small Grain Mixtures

A Look at Pea and Small Grain Mixtures

Mike Rankin
Crops and Soils Agent
University of Wisconsin - Extension

Perhaps not as common as they used to be, pea and small grain mixtures are still looked to as a viable forage source and companion crop for establishing alfalfa. Adding peas to the small grain will result in a slight increase in forage yield and improve forage quality (especially protein content). However, these advantages come with a higher seed cost.

Back in the late 1980’s, University of Wisconsin researchers did some extensive research with small grain – pea mixtures. Some of this work is summarized in Table 1. This research confirmed that the primary advantage of adding peas to the companion crop mixture comes with improved forage quality.

Table 1. Characteristics of small grain and small grain-pea mixtures harvested as forage and underseeded with alfalfa at Arlington, WI in 1986-88.
Forage Type	Cut date	Yield	CP	NDF	Alfalfa yield during establishment year¹	Total 1^st year forage yield²
	June	lb/a	%	%	lb/a	1b/a

Oats alone	12	3201	13.5	52.9	1915	5135
Oat / pea.	12	3441	17.6	46.3	1770	5191

Barley	8	3318	13.6	58.1	1779	5097
Barley / pea	8	3469	16.4	58.1	1577	5029
1 Alfalfa was harvested in mid to late August. To increase the probability of good winter survival, fall regrowth of alfalfa was not harvested in October in any year. 2 Total first year forage yield = forage yield from oats or oat – pea mixture harvested in June plus alfalfa yield harvested in August. Data from L.B. Chapko, M.A. Brinkman, E.T. Gritten, and K.A. Albrecht, 1989

The important keys to successful small grain – pea mixtures are as follows:

· Small grain variety selection: Especially among oats, there are big differences in varieties for both forage yield and quality. Adding peas to an exceptionally high yielding variety like ForagePlus is one way to offset its slightly lower quality.

· Pea variety selection: Pea varieties differ significantly in seed size. Make sure this is taken into account when determining seeding rates.

· Seeding rate: If mixing your own, seed about 40 lbs.of oats per acre along with 50 lbs. of peas (4 pea seeds/sq. ft.). Commercial mixes in a 50:50 ratio by seed weight are also acceptable.

· Harvest timing: Harvest small grain – pea mixtures based on the maturity of the small grain. Optimum quality is obtained when the small grain is in the boot to early heading stage. For heifers, dry cows, and beef cows, harvest can be delayed to capture more yield.

For more information contact Mike Rankin