imafan26 wrote:While there are only a few apple growing here we also have problems mostly with lychee of alternate bearing years. It seems that it has to do with the El Nino and La Nina. In LaNina years when it is cooler, the lychee bear better and the mangoes worse and the opposite is the case with El Nino. The El Nino cycles about every two years and that is consistent with the cycling of the fruiting trees. If it doesn't get cold enough no amount of fertilizer or girdling (which is the most common practice here for improving fruiting by stressing a tree), makes much difference.
Interesting to hear that 'girdling' is still used to control tree growth over there. This was used a lot here many years ago before better controlling root stocks were available. It was known as 'Bark ringing'.
On the modern 'intensive' plantings that are being used nowadays the same principle is being used by root cutting on alternative sides of the trees every few years.
Fully mechanised machines to do the job now, so no back breaking work!!
I guess the perfect growing conditions there make for a very rapidly growing tree, and as you say, not enough cold-temp for fruit initiation to take place...so all the tree has to do, is grow.