THORSBY, Alta. — There is drought somewhere every year.
To maintain forage crops in adverse conditions, it is important to always be prepared for the next dry spell, said a group of pasture specialists at a drought management workshop in Thorsby on April 19.
“We are constantly under drought management at our place,” said Ponoka rancher Brian Luce. He follows holistic management strategies and monitors grass production and cattle performance throughout the grazing season.
“We grow about 70 percent of our grass in the cool season country we are in, before the first week of July,” he said. “If we are coming into June without much growth, we have to make a decision where animals have to be removed.”
Read Also
U.S. cattle producers fear return of screwworm
Parasitic screwworm flies are pushing northward from Central America again after being officially eradicated from the United States in 1966, threatening $1.8 billion in damage to Texas’ economy alone.
He has learned he needs good grass before and during the breeding season because if fertility is poor, it affects next year’s income.
Last summer he ran out of grass and is now seeing reproduction issues within the cow herd.
He has combined his herd into one large group so there is one less paddock being used and that provides another day of recovery in another pasture.
He works to build up a good layer of thatch to keep the ground cool and moist but in some cases that litter is so thick it inhibits grass growth. Moisture is not penetrating as well as it should and that affects root growth. This year he plans to spread compost tea to get the thatch to decompose and turn into humus.
Good litter cover is like insulation for growing plants.
A 30-year-old study in the Alberta foothills showed a measurable forage decline when litter was removed. In the dry mixed grass region, forage production was cut by more than half when there was no litter covering the ground, said forage researcher Ed Bork of the University of Alberta.
Litter can hold snow melt moisture. Keeping the ground moist and cool may also keep out heat-loving grasshoppers.
It is also important to take care of the plant roots by controlling grazing patterns.
Grazing less than 45 percent of top growth has little effect on root development. If animals are continually eating, they chew away at the plants and roots, which drains the life blood of the plant, Bork said.
Root depth varies. Native plants have good, deep roots but tame species like smooth brome, orchard grass, Kentucky blue grass or timothy have more shallow roots.
“When we have a healthy vigorous plant with root systems that are deeper, greater ability to explore the soil horizon and get moisture out of it, it will be a drought avoider. It does not escape drought.”
Bork has also studied the effects of drought on forage across the prairies.
“It is no surprise as you increase the stress on the plants you get less herbage production,” he said.
Research shows drought impacts vary by region. The parkland region suffered a 43 percent yield loss when precipitation was about half of normal. The semi arid region in Saskatchewan showed little effect because the native mixed grasses have adapted to less moisture. Boreal grazing areas in Manitoba showed a 20 percent loss in forage under drought conditions.
One problem in many pastures is that they are old hayfields that are no longer productive. These are ill-equipped to deal with climate change because of poor soil fertility and few plant species.
Planning for this year’s grazing starts the year before. If a plant has lower vigour heading into the next year, its ability to regrow is diminished. Spring moisture can help mitigate some of the fall damage.
Grass may appear to be growing in spring but it is not the height of plant, but the number of leaves per tiller and carbohydrate storage that determine health, said forage specialist Grant Lastiwka of Alberta Agriculture. There should be at least three leaves per tiller so grazing should be co-ordinated to grass.
“Do not graze until it is ready.”
If this year continues dry, light or moderate stocking rates are rule of thumb, he said.
“We have to have grass growing to be in business,” he said.
There are no average conditions but it is important to realize a 60 percent drop in moisture causes a 35 percent reduction in yield.
Drought management tips and research results have been coordinated into a single website for producers looking for specific details on forage production.
The information may be found at www.foragebeef.ca.
