A plant growth regulator just on the market can be a “very useful tool for shifting production to early spring or extending grass production several weeks in the fall,” according to university research.

Called RyzUp SmartGrass, the growth regulator is a dry formulation of gibberellic acid, used in targeted applications to forage during cold-weather stress. It is manufactured by Valent U.S.A. Corp. and was introduced during last month's World Dairy Expo in Madison, WI.

“Applied to pastures in early spring or late fall, the product will promote higher growth rates at suboptimal temperatures, allowing increased stocking rates and shortened rotational intervals for forage when used in an intensively managed production system.” That's according to research led by R.P. Kaiser, Valent development manager; Marvin Hall, Penn State University extension forage agronomist; and Richard Leep, extension forage specialist with Michigan State University.

Trials conducted in the fall of 2008 demonstrated the importance of correct timing for maximum benefit, the researchers say. Applied in early September in Pennsylvania, the growth regulator did nothing. But applications made later in the month, when first frosts and cold weather occurred, resulted in 40-140% increases in dry matter yield. In Michigan, applications began in October, but a 50-lb/acre application of supplemental nitrogen was added. Dry matter increases 21 days after treatment ranged from 22% to 42% on plots without added N and from 88% to 150% in plots with N.

When moisture and nutrition are adequate but temperatures are cool, RyzUp SmartGrass can produce extra grass growth in instances when normal grass growth is minimal, the researchers conclude.