Summer Seeding Oats & Oat-Pea Mixes
Summer seeding annual forages can be a useful low-cost option for producing extra feed, either as an emergency forage or a regular double-crop option. These forages include Italian ryegrass, cool-season cereals (oats, barley, triticale) and cereal-pea mixtures, as well as some warm-season sorghums, sorghum-sudangrass and millets (pearl, Japanese), but some are more successful than others.
Record acreages of these emergency annual forages were seeded in the drought year of 2012, and provided farmers with a “big save” in meeting their forage needs. Yields and nutrient quality were generally good, with high volumes of palatable quality baleage and silage made. An early winter wheat harvest provides a bigger window for timely summer seeding of these forage crops.
Oats have been frequently used, as a low cost, low risk approach. They can be seeded in late-July or early-August following wheat and spring cereal harvest for an early-October harvest.
Oats can make good feed when harvested at the correct stage of maturity and made into “oatlage” or baleage. Oats are more frost tolerant in the fall than sorghums, and can continue growth after some frost. The challenges can sometimes be lack of adequate moisture in August, and having dry enough weather in October for adequate wilting. Crown rust is also a potential risk. Rust can defoliate the oat crop and decimate yields if infection is severe. Oats can be strip-grazed if fence is available.
Oats, Barley, or Triticale? Many find that oat forage is the most palatable of the cereals. Oats tend to out-yield barley, triticale and spring wheat when establishment conditions are poor, such as in hot, dry summer seedings. Some producers avoid barley and triticale in baleage because of concerns about the awns. At the same stage of maturity, oats, barley and triticale are very similar in feed quality. Of the cereals, oats are often the most readily available, and usually give the best yields and returns for the dollars invested.
Oat-Pea Mixtures Peas can be added where higher forage quality is required to meet livestock needs. Cereal-pea mixtures are popular as a spring seeded companion crop. Peas added to cereals improve forage quality, but do not necessarily increase yields. Summer seeded peas dislike hot, dry conditions even more than cereals. Pea growth is often quite variable depending on moisture. Peas are more succulent and higher in moisture than oats, and can be very difficult to wilt in the fall. Pea mixtures may lie in the swath for an extended period of time with the risk of being rained-on. Lush cereal-pea mixtures can be difficult to cut. Pea seed costs more. Despite these concerns, peas improve forage quality where meeting high nutritional requirements is a priority, such as for dairy cows.
A mix of 70% oats and 30% peas, such as QS “Fall Buster”, is a good compromise for fall harvested forage, balancing improved forage quality with the increased challenges of harvesting peas in wet fall weather.
Cereals Versus Sorghums or Millets? Sorghums are much more tolerant of hot dry summer weather than cereals. In situations where seeding dates are very early (early-July) allowing for harvest maturity (50 – 60 days) before frost, sorghums will yield better than cereals. As cool-season grasses, oats are not very tolerant of hot dry weather and do not tiller and grow well in these conditions.
As days shorten in the fall, so may require an additional 10 days, so about 70 days will be required. Oats seeded on August 1st would typically be ready to harvest in early-October. Many prefer to no-till drill oats into wheat stubble to save time and moisture. Alternative seeding methods are to broadcast the oats and then incorporate them with a light disc or cultivator, or to seed into a prepared seedbed using a conventional drill. Summer seeded oats for forage are commonly seeded at about 65 – 100 lbs per acre (2 – 3 bu/ac). The suggested rate is usually 70 lbs/acre. High seeding rates have little impact on improving yields.
Seeding after winter wheat is harvested can be a good opportunity, but competition from volunteer wheat can be a significant problem. Without vernalization (going through a winter) winter wheat will not form a stem in the fall to provide significant growth and yields are very limited. A lot of volunteer wheat can result when light grain goes through the combine, such as fusarium infection situations. One approach to reduce the problem is to do some light tillage (at least behind the combine swath) to encourage the grain to germinate. A burndown with glyphosate 7 – 10 days later will remove much of the volunteer grain.
Harvest Moisture & Fermentation Wilting late-summer seeded oats to an acceptable moisture level to allow for a good fermentation during October weather can be challenging. Fall weather tends to be cooler, days are shorter, dews are heavy, and “rain delays” while lying in a swath can be significant, resulting in much slower and more difficult drying. Heavy crops and cereal-pea mixtures are especially challenging.
When making baleage, ensure that there is adequate plastic wrap used to ensure that it is anaerobic. As an alternative, strip grazing the growth in late-fall can be a good way to harvest late planted annual forage and avoid the challenges of making wet silage.
Forage Nutrient Quality A common question is “what is the forage quality of these summer seeded forages?” This depends entirely on:
1. maturity at harvest, as well as 2. acceptable moisture levels for successful fermentation.
Cereals harvested at flag-leaf or boot-stage will be higher nutrient quality, but lower yielding than cereals harvested at late-head or soft-dough stage. When peas have been added to cereals, nutrient quality can be very high.
Stage of maturity for optimum forage quality is at the “boot-stage” (head beginning to emerge from leaf whirl). Harvested at the boot-stage, fall grown oats are highly digestible and palatable. With cooler temperatures and shorter days, fall grown oats often have higher digestible energy than spring seeded oats. Boot-stage oatlage is excellent feed for dairy heifers and beef cows, but may not be adequate to include in high producing dairy cow rations. At the boot-stage, cereals are typically about 16.5% crude protein and 54% NDF with very good fibre digestibility.
Once headed, nutritional quality declines rapidly. Harvesting at the headed stage will provide more yield, but will have much lower digestible energy and protein. Use wet chemistry rather than NIRS laboratory analysis of cereal forage.
There are sometimes a few reports of high nitrate levels. When this is a concern, testing for nitrates is recommended, particularly if this forage makes up a high percentage of the diet. Refer to “Potential Nitrate Poisoning” http://fieldcropnews.com/?p=4976 .
Yields Highly Variable Yields of summer seeded cereals are highly variable, but under good conditions dry matter yields can typically be in the 1.25 – 1.75 tonne/acre range or more. In years of tight forage supplies, every bit counts. Cereals can be a good low-cost emergency forage option if timely rainfall is received for germination and growth.
By: Joel Bagg, Forage &
Development Specialist & District Sales Manager, Quality Seeds Ltd.