Skip to main content
ARS Home » Research » Publications at this Location » Publication #126052

Title: FORAGE FROST PROTECTION POTENTIAL OF CONIFER SILVOPASTURES

Author
item Feldhake, Charles

Submitted to: Agricultural and Forest Meteorology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/22/2002
Publication Date: 10/5/2002
Citation: Feldhake, C.M. 2002. Forage frost protection potential of conifer silvopastures. Agricultural and Forest Meteorology. 112:123-130.

Interpretive Summary: In much of the United States spring and autumn forage growth is limited by episodic nighttime frosts. This limits animal grazing and increases the reliance on stockpiled feed which increases farmers' expense of production. A sensor was designed to approximate forage temperature during frost events. A series of these installed within a pasture containing pine trees showed that forage temperature was up to 18-degrees F warmer during frost events when most of the open sky was blocked by pine foliage. These results suggest that appropriately spaced pine trees may extend spring and autumn grazing times. This work is useful for researchers designing innovative grazing systems as well as for farmers who ultimately utilize them. It will benefit the agricultural community by reducing energy use and the associated expense, and by saving time and equipment wear. Extending grazing times also reduces waste handling and the associated environmental liabilities.

Technical Abstract: Pasture forage availability for grazing animals in temperate regions is limited by cold temperatures which restrict plant growth. The transitions from cold weather to warm growing season can contain episodic severe radiation frosts where air temperature is otherwise suitable for plant growth. Protection from these frosts could extend the grazing season, thus sreducing the need for mechanically harvested forage. A sensor for quantifying night time thermal radiation balance of forage canopies was designed, tested, and proven to be accurate. The effectiveness of conifer trees to block radiation cooling of forage understorys on clear nights was measured. Trees facilitated forage temperatures remaining up to 10 degrees C warmer under dense stands compared to open fields. Tree stand density was linearly correlated with temperature. This work is useful for helping agriculture researchers design silvopasture systems that optimize light availability for growing forages in cool weather while providing a desired degree of protection from damage to forages due to radiation frost. This information will benefit rural economies by changing forage management systems to reduce adverse impacts of weather, during transitional season periods, on forages available for animal production systems.