Poink88, regardless of Gary's thoughts about your posts, I am curious just as a learner. Below, I've paraphrased what you said earlier to make it a little clearer for myself (and maybe others?):
With a cutting, if you take a cutting as the buds start to swell, the branch still has stored energy that it can use to grow both roots and leaves. If you wait until the leaves are out, the cutting might not have enough energy to produce roots. Leaves also transpire water, and without roots, the leaves that it used its energy to produce will most likely be lost.
With air layers, on the other hand, the branch still has a supply of nutrients from the parent tree.
And here are my two questions about the different times for different methods:
1.Are you suggesting that if an air layer were started as the buds start to swell, that it would not be able to use its stored energy to grow roots and leaves? If so, why not? Or is there another reason that air layers shouldn't be started as buds start to swell?
2. On the flip side, are you suggesting that if cuttings are taken after new leaves have hardened off, that, unlike an air layered branch, its leaves would
not be able to assist in the production of roots? If so, why not?