I was excited to finally see growth on the north side of my 2 yr.old DM Palo Verde, only to discover these new limbs have thorns. I didn't think it was a grafted tree when I got it from DBG...should I leave it alone, or prune the thorny limbs off? If I cut, the tree will be lopsided again...
Thanks for any info you can give.
beanieb, I had 3 huge DM Palo Verde in my yard. None of them ever had thorns on them. Actually didn't know that the DM had grafts. I'm not sure, but if they do, and you simply remove the limbs/stems that have the thorns, if they came off a main trunk, Then any new limbs that come out again, should have thorns too. If the thorns are a real problem for you, like they would be for me, then you may have to replace the tree. Honestly, I have never heard of a DM Palo Verde with thorns. Is it possible that you were sold some other PV? By the way, my DM got so big I had to have them thinned out every year. Cost a fortune. Even then, the winds finally got to it and it split right down the middle. It was only about 6 years old.
Beanieb, like cactusjumper I also used to have 3 DM PVs in the front yard. I am down to one tree, and two returning 'bushes'. The trees got so big that eventually during a very rainy windy day one went, which had been providing the wind shadow for the other that went a few weeks later due to another storm. I rent the house I live in and the landlord did not want to pay to get the stumps removed, nor to get them pruned, so they were left and now barely two years later I have what I would call bushes, where the stumps were. I am trying to keep them under control but they grow so fast when they get rain it is incredible. The third tree is still standing, but it is so massive that I will likely have to pay an arborist to do a professional pruning (cut back) job on it - and I am worried about it every time we get some major weather, especially if one of the neighbors' visitors has their car parked under it. But to get to my point, I did notice on the new growth from the stumps the occasional, what I would call, vestigial thorn, nothing extremely large or serious, but thorns none the less. I have not noticed any during my recent pruning activity, but I will have another good look this weekend when another round of pruning is due.
Reading up on DM PV it was not grafted, but was found to be a complex hybrid that has genetic material and aspects of several different species including 3 different Palo Verde species in it and was thornless. The DM PVs were cloned/propagated from one original thornless seedling, which was started in the late 70s. I can imagine that the genes that make it grow thorns could become re-activated, as they are surely present somewhere in the genetic code of the tree. Not sure why that would happen, but as far as I can tell it is not impossible.
This might suggest that cutting the branches with thorns off might solve the problem. How big are the thorns?