To bloom or not to bloom?

By Kassidy Buse

A common recommendation of agronomists is to let one alfalfa cutting reach bloom each year.

Ev Thomas, retired agronomist from the Miner Research Institute in Chazy, N.Y., says otherwise in The William H Miner Agricultural Research Institute Farm Report.

“For many years, I’ve said that in managing alfalfa for dairy cows, you should never see an alfalfa blossom, from seeding to plowdown,” says Thomas.

Thomas also notes there’s room for difference of opinion due to no research supporting either opinion.

But, if one cutting is to bloom, which cutting should it be?

The first cut of alfalfa-grass typically contains the most grass. Grass, even the late-maturing species, is close to heading when alfalfa is in the late bud stage.

The second cut is exposed to long, hot June days that result in highly lignified, fine stems. A Miner Institute trial found that the stem quality of bud-stage second-cut alfalfa was no better than full-bloom first-cut alfalfa.

The third cut can be influenced by prior harvest management. If it was a late second cutting, the third cut was growing during midsummer heat. This cut would also have highly lignified stems.

The fourth cut often takes a long time to bloom, if it makes it there. A killing frost might arrive first.

For any cutting, the more grass in the stand, the lower the forage quality if alfalfa is left to bloom.

“The objective of letting alfalfa bloom is to improve root reserves, and therefore extend stand life,” says Thomas. “We need to balance the impact of delayed harvest on plant health with the economics of feeding alfalfa of lower quality that is needed by today’s high-producing dairy cows,” Thomas adds.

How alfalfa and alfalfa-grass is managed depends on if the goal in mind is long stand life or high milk production potential.

Protecting Your Animals This Summer

As it gets further into the summer months, livestock begin to show express a common discomfort as humans do: sunburn. Exposure to UV radiation can cause skin damage to dairy cows, light-colored beef cattle, sheep, pigs, and horses. Affected skin becomes red, painful and raised, which can lead to the skin becoming extremely dry and will eventually slough off leaving those areas exposed to secondary infections.

A cow losing patches of its coat due to sunburn
A cow losing patches of its coat due to sunburn

Sunburn not only makes the animal uncomfortable, it affects their overall productivity and performance. The body takes the nutrients that is needed for growth and uses them to repair the skin that is damaged. In dairy cows, this can lead to a decrease in milk production and in sheep, a decrease in wool quality. Sheep can be burned sheared or unsheared since the radiation is strong enough to penetrate through the wool. Pigs are one of the lucky animals that can protect itself form the suns rays. By wallowing in mud, the pig is forming a protective coating that shields the skin from the sun. Light coated animals are not as lucky. Cows and horses with predominantly white coats suffer more sunburn than those with dark coats. However, dark coats absorb more sun, which leads to more symptoms of heat stress.

UV radiation isn’t the only determinant of sunburn in animals. Animals that feed in wheat pastures with certain weeds are likely to develop photosensitivity. This is caused by a reaction within an animal’s body when the chlorophyll in some wheat plants release a toxin that increases sensitivity to the sun. Weeds such as barley, alsike clover, St. John’s Wort, nettles and others are some of the culprits in photosensitivity and can also be the causes of liver damage and neurological disorders that develop in the animal.

Preventing sunburn doesn’t just mean keeping them out of the sun, although providing a shady place for the animals can definitely help. If the sun is a concern, baby formula sunscreen can protect the areas that are more vulnerable to sunburn. Another way of decreasing sunburn is restricting the access of wheat pasture the animal is consuming to prevent photosensitivity. Adding grass hay in the morning when grazing intake is high helps in restraining the animal from consuming too much wheat during those times.

Nutrient Management Credits Offered at Upcoming Pasture Walks

The University of Delaware Cooperative Extension is offering pasture walks in two locations this spring.  Participants will have the opportunity to earn nutrient management and pesticide certification credits.  The first walk is being held on May 28th from 6:30-8:30 pm and is being hosted at the farm of Rick and Kim Vincent of Harrington and the second walk will be on June 4th from 6:30-9:00 pm at the University of Delaware’s Webb Farm in Newark.  Program agendas are listed below.  Participants are welcome to bring a plant or weed sample with them for identification.  Please pre register if you plan on attending either program.

Past Participants with Forage Sticks
Past Participants with Forage Sticks

May 28th Pasture Walk Hosted by Rick and Kim Vincent

3427 Burnite Mill Rd. Harrington, DE 19952

6:30-8:30 pm

Welcome and Introductions– UD Cooperative Extension Staff

Farm Overview/Current Pasture/Grazing Management– Rick and Him Vincent, Hosts

Pasture Plant Species ID– Dr. Richard Taylor, Extension Agronomist

Soil Fertility and Pasture Health– Dr. Richard Taylor, Extension Agronomist

Weed ID and Weed Control in Pastures– Quintin Johnson, Extension Agent Weed Science

Soil Sampling Techniques, Sample Submission and Testing Options– Bill Rohrer, Owner and Manager AgroLab

DE NM Credits 1.25   Pesticide TBA

To register for this pasture walk, please call (302)730-4000 or email truehart@udel.edu by May 27th


June 4th Pasture Walk Hosted at the University of Delaware Webb Farm

508 S. Chapel Street Newark, DE 19716

6:30-9:00 pm

Tour of Pastures and Management, Pasture Renovation Techniques – Larry Armstrong, UD Webb Farm Manager

Soil Fertility, Plant ID, Bermudagrass Establishment – Dr. Richard Taylor, Extension Agronomy Specialist

Weed ID and Weed Control in Pastures – Quintin Johnson, Extension Agent, Weed Science

Soil Sampling techniques and Proper Sample Submission- Karen Gartley, UD Plant and Soil Science Research Manage

Overview of NRCS Programs- Marianne Hardesty, New Castle County NRCS District Conservationist

DE NM Credits 1.75 Pesticide TBA

            To register for this pasture walk or  request more information, please call (302)831-2507 or email severson@udel.edu by May 30th