So the bloom is finished, and the bees have moved on to their next jobs on other farms. The apples are growing larger every day. But if all the blossoms on an apple tree turn into apples, the tree would never be able to support them all! And the resulting crop would look like bushels and bushels of little red golf balls!
Some of the blossoms, however did not get pollinated. So those will not turn into apples. Some may have winter or spring cold weather damage and will not develop. And sometimes the tree, knowing how many apples it is carrying by sensing the volume of a hormone produced by each apple seed, will abort some of the apples in order to survive. (See my prior blog on Gibberellins). If left alone, apple trees will often have a big crop one year and a small or no crop the next. We growers realize that in order to have a decent crop year after year, we have to try to smooth out that cycle to have a moderate crop every year.
There is a short window of opportunity after bloom in which we can help the tree cast off some of it’s fruit if it is carrying too much. But at that point, we still don’t know just which fruits are going to continue and which will stop and fall off. That’s where apple measuring comes into play. For several years now, my daughters, Tressa and Taylor, have taken on the task of measuring fruitlets every three days over this period. First they mark 75 fruits on each of 5 trees in each orchard that we are tracking.
Then they measure each fruit with a digital calipers and record the data.
It is a time consuming task, repeated every 3 days in each variety that we want data on.
The data is entered into an Excel spreadsheet program. After 3 or 4 sets of data have been entered, we can crunch the numbers and the program will tell us which fruits are growing and which are slowing down and are going to eventually stop. This is a huge help to us in determining the eventual size of the coming crop, and with this information we can decide whether to leave the tree alone or to “help” it to cast off some of it’s fruit. We can do that by applying some products that stress the tree slightly so that it will decide it can’t carry quite so much. The tree will then kick some more fruit off and help regulate the crop.
The process isn’t as easy as it sounds. There are many other factors involved; tree health, weather, and previous year’s crop all play a role in the big picture of crop size and the response that we may get when we try to”help” the trees. But the many hours of work and thousands of measurements that these girls take are an invaluable resource for us, making a difficult decision making process more precise. Hats off to them!!
Just another example of how technology and hard work are changing farming for the better!
Have a fruitful week!