Traditionally, forage stands are terminated in the fall so that a good seedbed can be established and the sod root system has some time to decompose. However, hay stands can also be terminated in the spring. Producers just need to be aware of a number of factors that can impact success.
Spring termination of hay land will delay the seeding date two to three weeks. In order for herbicide applications to be effective, sufficient plant material must be present. Grasses should be at the three- to four-leaf stage and legumes need to be actively growing to allow for good herbicide coverage. Seeding will need to be delayed three to five days after the herbicide application to allow thorough translocation into the plant.
A number of factors will influence the type of annual crop to be seeded. With sod seeding, the most consistent results have occurred with cereal crops such as barley or oats. The larger seed size with cereals allows seeds to be placed beneath the thatch layer into soil where good soil to seed contact occurs. Crop competitiveness must also be considered. Seed quality, seeding rate, seeding depth, crop height and fertilizer placement are all factors that producers need to consider.
Soil moisture must be managed properly. In many areas of the province, conservation of spring moisture is essential for crop establishment. Direct seeding into sod will retain available soil moisture that would be lost if multiple tillage operations were used to prepare a seedbed. Even with direct seeding it is important to recognize that available soil moisture will be reduced as the forage species grows to an appropriate stage for spraying. Moisture conditions at the time of seeding must be evaluated, as does soil fertility.
It is important to remember that late-seeded crops will have a shorter growing season to produce grain. In these situations, seeding a crop that can be used for silage or green feed offers a viable end use for these fields.
A factsheet answering many questions about spring termination of hay land is available on Alberta Agriculture and Rural Development’s website under Frequently Asked Questions.