In 2017 we harvested around 400 17yr old Indian Sandalwood trees. When cutting down the trees I keep an eye out for any trees which show exceptionally good quantity of heartwood as a % of the diameter and also those that have heartwood high up the tree (up to 5m). I'm also looking for the tree to be straight and a larger than average diameter. The estimated oil yield needs to be >3 times the average.
If I find one that meets these criteria then before the leaves wilt, I cut off a bunch and put them in the fridge and then get them to the local nursery before the end of the day. These are grafted onto root stock to capture the genetics. Some of the grafted trees are planted in seed orchards to try and get seed pure to the parent. Some are being multiplied to be grown in the 2018 planting and some are being used to attempt to clone them.
In 2016 I selected 2 Superior Trees and in 2017 I selected another 10 trees. Hopefully this will dramatically improve future yields.