Breeders release trees that set fruit with less work
By JOHN SCHMITZ
For the Capital Press
A development taking shape in California almond orchards could prove to be a big change for orchardists.
For about two years, growers have been snapping up the limited but growing supply of recently developed self-pollinating trees.
"It's creating a stir," said Bob Curtis, director of ag affairs for the Almond Board of California. "It's a milestone that will continue in the industry."
Dennis Tarry, CEO of Dave Wilson Nursery in Hickman, Calif., said that demand for the nursery's proprietary Independence variety, which was developed by Zaiger Genetics, has been high.
The chief reason growers are buying his budded Independence trees, he said, is that they eliminate the need for lower-paying pollinizer varieties that often must be harvested at different times.
What's more, Independence "lessens the pressure for bees," Tarry said. "We have set commercial crops in tented replicated trials with bee-free environments."
In those trials, one midsize dormant hive per acre set even more nuts.
There's some discord in the industry as to whether to call the new hybrids "self-compatible," "self-pollinating" or "self-fruitful." According to University of California-Davis pomologist Tom Gradziel, the terms are related.
"Self-fruitful indicates that an almond flower can effectively self-pollinate itself and that the pollen will be self-compatible (or set fruit)," he said. "Self-compatibility is determined by a single major gene and so is relatively stable over years and locations. Self-pollination, however, is controlled by a large number of different genes which can result in differing levels of performance in different years and locations."
What label will eventually apply remains to be seen as the trees mature in young orchards.
Burchell Nursery in Oakdale, Calif., has also invested in self-fruitful almond trees, but is taking a slower approach to making stock commercially available.
"We're only putting trees out for experimental use right now," owner Tom Burchell said. "We don't want to sell acres and acres of them until we know their productivity, seeing as how they are self-fruitful."
Burchell Nursery has four different proprietary varieties, all developed in-house, that are in trials with a dozen or so growers. Once the figures are in the budded hybrids will be patented and released.
"It's going to take probably another couple of years," Burchell said.
He believes that pollinizers will still be needed to maximize almond production in self-fertile orchards. However, the pollinizers could be of the same type and the entire crop could be harvested at the same time.
Also, fewer pollinizers would be needed.
As for pollinators, "we still recommend bees, but not as many," Burchell said. "We're still in the experimental stage, but we think maybe half."
Tarry said that Independence, which was made commercially available 2 1/2 years ago, is his No. 2 seller overall, behind the industry standard Nonpareil. He expects to have sold as many as 650,000 Independence trees, enough to plant 54,000 acres, by the end of this fall. Each tree bears a $1.50 royalty.
Many growers are finding a "significant crop" in the tree's second leaf, Tarry said.