Pasture and Forage Minute: Toxic Plants and Grass Hay Timing
Poisonous Pasture Plants
While generally not as problematic in Nebraska compared to other western states, poisonous plants can exact their toll on livestock enterprises, and many times the losses are unrecognized.
There are 17 species listed as primary toxic plants that can be found in Nebraska. Toxic plants contain or produce substances injurious or lethal to animals. The amount of plant material consumed by the grazing animal before death or poisoning symptoms appear, does vary by species. Poisoning symptoms will vary depending on the toxic compound in the plant, but may include difficulty breathing, excess salivation, nervousness or staggering. Many poisonous plants are avoided by the animal, but a scarcity of forage — such as under drought conditions — may lead to a situation where they are consumed.
There are some species, such as prairie larkspur, where grazing animals may select for them when they are flowering (mid-June to early July). Other relatively common poisonous plants in central and western Nebraska include Riddell groundsel, Lambert crazyweed, wooly locoweed and chokecherry.
Poison hemlock and spotted water hemlock are common statewide. These two species prefer moist areas in pastures, creek banks, ditches and disturbed sites.
If you suspect a poisonous plant problem in your pastures, be sure to get a positive identification of the plant. When control or removal of the plants is not possible, it may be best to move livestock to a different pasture.
Nebraska Extension does have a great resource called Nebraska Plants Toxic to Livestock (EC3037), which can be found online or obtained through your local extension office.
High Density Stocking
Warm temperatures have pushed many cool-season grasses to maturity quickly, ahead of our grazing rotations. Can changing your grazing strategy help use this mature forage more efficiently?
A big pasture management challenge is keeping grass from heading out, becoming less palatable and low quality. If we rotate animals the same as earlier in the year with all the headed out grass, animals will strip some leaves, trample a lot of forage and leave most of the stems standing. They will probably end up eating less than one-fourth of the potential forage available.
With forage looking like a valuable commodity this year, getting animals to eat a bit more now by limiting how much choice they have could be beneficial. Instead of giving them the entire paddock to graze, use electric fence to limit them to very tiny areas at a time.
How tiny you ask? Well, one possible initial goal would be to put the equivalent of about 250,000 pounds of cattle on just one acre, about 150 to 200 cow-calf pairs per acre. Obviously, it won’t take them long to finish off that small area, so expect to give them a fresh strip as many as three times a day. With the high density of animals, grazing distribution will be more uniform and you could see an improvement in grazing efficiency.
Keep an eye on animal condition and adjust the paddock as necessary to find a good balance between grazing efficiency and meeting nutritional demands, especially with growing animals and those with high nutrient demands from lactation.
Getting water to the animals can also be a challenge, so I suggest letting them walk back to water over previously grazed strips for a couple days before changing water locations. It will take a little adjustment to get just the right size and water placement, but after a couple days it should go smoothly.
If all goes well, you’ll get more cow-days of grazing with less waste.
When to Cut Hay
Bromegrass is headed out and native meadows are beginning to grow rapidly with warmer temperatures the past couple weeks. Is now the time to make grass hay?
Sometimes a simple date on the calendar is the reason hay is cut. Some will cut when it works in their operation; after corn is fertilized or sprayed, after branding or turning out to summer grass, maybe after kids’ baseball and softball seasons are over. Tradition and schedules play a key role in management decisions, but should we consider another factor?
An important, yet often overlooked way to determine when to cut, is what quality of hay is needed on the operation. Is a protein source needed to minimize supplementation? Is simple roughage needed? Will it be sold? Can it be sold at a premium for being higher quality? Each operation is different and has different needs.
Right now, the quality of bromegrass and other cool-season grasses is rapidly declining. As these plants mature and become stemmy, their protein, energy content and digestibility decrease. Studies have shown that grass hay cut at early heading could result in a daily gain of one pound for bred heifers whereas the same mature hay may not even meet the requirements of a dry cow.
When deciding when to cut or what field to cut, first determine what livestock will consume the hay and plan accordingly.
A little change to the timing of haying might better meet livestock nutrient requirements and reduce supplementation costs.