Stretching out the Spring Flush of Forage Growth

Chris Penrose, Extension Educator, Agriculture & Natural Resources, Morgan County

For most of us, forage growth has finally started and we are getting the spring “flush” of growth. For pasture and hay fields that are primarily grass based, we may get up to 70% of our growth in the next month or so. One reason we have so much growth now is that we generally have ideal growing conditions and our forages are in the reproductive stage of growth. The main priority for our perennial grasses and legumes in this stage of growth are to make seed heads. For our grasses, this will most likely be the only time seed heads are made, which will be during the next month for most grasses. As forage managers, we have two tasks to improve our grazing during this time of the year.

First, if we can remove the seed heads, the forages will move from the reproductive stage to the vegetative stage. This will stimulate new leaf growth and encourage the plants to start storing energy in the roots to help them through the summer stress and into the winter. A mature plant with a seed head on it will not grow as well and be of lower quality from being mature and having lower quality stems on it.

How do we remove seed heads? There are two options: have the animals remove them or cut them. Unfortunately, many grasses set seed all at once and that becomes a challenge for livestock to graze off. If the plant is starting to develop the stem that has the seed head in it, livestock may graze the tender seed head in the young stem. Some animals like goats my enjoy grazing the seed heads, but cattle may not graze the stems and seed heads in favor of the leaves at the base of the plant. Forcing animals to graze mature forages can adversely affect animal performance. If pastures get too mature, a good option is to simply clip them after seed heads have emerged. Another option if forages are growing too fast may be to set aside the field and remove the crop for hay later on.

What is the other way to improve our grazing this time of the year? Try to stretch out this flush of growth. If your pastures are healthy enough after last year’s drought and growth has started, you can do a rapid grazing through the paddocks and slow down slightly the growth when the rapid growing begins. Another option may be to set stock (giving the animals the run of some to all of the paddocks). Then as the rapid growth slows down, initiate a rotation, possibly leaving some paddocks for hay removal if you anticipate excess pasture and need hay.

If you are short on pasture and have available hay fields, light grazing over hay fields, especially predominantly grass fields may be an option. I have grazed grass hay fields for over twenty years early in the spring and as long as I get livestock out prior to stem elongation, I still get a decent hay crop (there was one year I made a final pass in late April and we had virtually no rain through May: I had a poor hay crop that year). Another advantage to this is the hay will likely mature a little later providing a better quality hay crop. If you do this, do not overgraze, and if cattle are grazing on the hay fields, avoid keeping on too long during wet weather to avoid “pugging” of the field.


Mid to late May orchard grass and fescue field above that was grazed in April (photo by Chris Penrose)

A third option, which is more long term, would be to use different cultivars of the same species in in different paddocks as you reseed fields. As you can see in the picture of orchard grass, different cultivars can have different maturity dates which can stretch out the flush of new growth. In addition, new and improved varieties have improved quality, persistence, and insect and disease resistance. If you are considering a new planting, I highly recommend purchasing the best seed available. The additional cost is minimal when you consider the total cost of the seeding and how many years the forage should be in a stand. This will allow different maturing dates and lengthen the spring flush of new growth.

Each of us is in a different situation. Some may be very short on hay ground and have plenty of pasture, some may be just the opposite. One of the most important aspects of Managed intensive Grazing is to be flexible and try to anticipate what the forage needs and availability will be over the course of the season. Hopefully a few of these options will allow you to have a more successful grazing season.


Early maturing orchardgrass on the left, later maturing on the right (Photo courtesy of Dr. Mark Sulc, OSU Extension Forage Specialist)