As alfalfa stands age, they also thin out. Unfortunately, it is not just older stands that thin with age. Younger stands can thin out, as well, leaving many producers wondering what can be done to strengthen these stands.
One option to consider is overseeding alfalfa into alfalfa. The hope is that by doing so, the life of the original alfalfa stand will be prolonged and any deficiencies in the stand will be corrected. While this method works in some cases, it is not a sure thing. If you are a producer wondering whether to overseed thinning alfalfa stands here are three greatest risks:
As a slow-growing perennial, alfalfa has a difficult time competing with existing plants and weeds for things like water, nutrients and water. Further, soils in fields that are well established do not germinate well.
If the reason for plant loss in the first place is not determined than it is likely that it will impact the newly planted alfalfa, as well.
Alfalfa produces autotoxins that suppress growth of alfalfa seedlings in existing stands.
There are times when overseeding alfalfa stands is more likely to produce good results. If stands have been damaged by flood or frost than overseeding is likely to work well.
If you decide to over-seed alfalfa, it is important to keep a few things in mind. One, if you are overseeding alfalfa into young stands, pay close attention to herbicide limitations, seed depth, tillage and timing. Also, while overseeding into older stands is less successful it is still possible under mild conditions.
If you decide that overseeding is not the right option for your operation, there are other methods to improve thinning alfalfa stands. One effective method is to overseed with grass forage such as berseem clover, fescue, oat hay, orchard grass and ryegrass. These types of annual and perennial forages are planted in the late fall or winter and will quickly grow and push through dormant, established alfalfa to fill in thinning and weak stands.
Keep in mind that when overseeding with grass forage mixed hay may not be acceptable for livestock feed for the dairy industry. Instead it should be fed to horses. Finally, when grasses are mixed with alfalfa, the grasses will take over alfalfa over time.