2007 marked the 12th birthday of the Phase 1 block (as measured from germination) and the 9th birthday of the Phase 2 block. Past attempts to coax the youngsters into flowering have met with limited success, but now they are beginning to show more of a natural interest in the other trees! Last August's 90-bushel harvest was a modest, but significant step toward steady seed production.
The
seed has not been processed yet, so the yield of last summer's harvest is not
known at this time. I'll be interested in the pounds/bushel statistic because it
indirectly measures how well the trees pollinated. There seemed to be an
abundance of pollen clusters, but it's hard to say if there was really enough
pollen in the air to fill the cones with seed. In an unscientific experiment, we
dusted pollen onto the flowers of some trees and allowed other trees to
pollinate without human assistance. The two seed lots will be compared to
determine whether it's worth trying to boost seed production in this way.
Meanwhile, we're talking with our counterparts to the south and east who are doing formal experiments with flower stimulation in ponderosa pine. One thing they've learned, by accident, is that lower rates of gibberellic acid may actually produce better results. This relieves my concern about excessively stressing the trees, so we decided to resume the stimulation schedule using a lower concentration of GA. This was done with treated vs. control groups to help us decide whether the results justify the extra workload of applying GA during the busy summer season.
We gained valuable experience last summer by having our own people harvest the 90 bushels of cones. Before long, the task of picking larger crops will have to be turned over to contract crews. One lesson we learned is that Valley Pine's shaggy foliage makes it very difficult to find the cones. It will be a challenge to make sure the contractors do a good job of clean picking, which is important for maximizing yields and controlling insect populations.
Our crew recently thinned and pruned the Phase 2 block and disposed of the slash to prevent insect attack. The Phase 1 block is already in need of another thinning because the trees are growing so rapidly on our soil type. This time we will need to balance seed production and gene conservation objectives, as some families may need to be reduced in numbers to maintain open spacing.
In the way of pest control, We are working with ODF entomologist Rob Flowers to confirm the identification and evaluate control measures for an insect believed to be the western pine cone borer. Damaged cones were found throughout the orchard, with certain trees having a higher concentration. We've also seen evidence of red turpentine beetle on a few trees. This will be monitored, and insecticide will be applied as needed.
Finally, a safety note to anyone working "up close" with Valley ponderosa pine. Be aware that the long needles pose a hazard to the eyes. They can even work their way behind safety glasses!
