I mentioned last time how good–with one sorrowful exception–the Italian cypresses in the main quad are looking. All kidding aside, it’s really nice to see them apparently thriving. There’s another sad tree situation to report, though. The beautiful Chinese pistaches on the east side of the old Physics Building are coming to their own end. Here’s a photo I took of them in December of 2013:
About a month ago I turned that corner and was shocked to see the state they’re in now. I’m not a tree expert but this does not bode well:
So when I ran into a grounds guy a few days later I asked him about it. He didn’t know but in no time flat I got an email from Dawn Ehlinger, Rice’s chief arborist. I’m very grateful to her for taking the time to fill me in even though it’s bad news:
Good afternoon, Melissa. I’m Dawn Ehlinger, lead arborist here at Rice – we chatted a bit when I first got here back in 2019. Danny Kruse on our moving team says he ran into you and you asked about the very sad pistache trees. And they are very sad. And we know they’re very sad but unfortunately we can’t fix them.
They are a Texas Superstar plant – drought tolerant, put up with heavy clay, lovely fall color, just an all around good tree – and I routinely recommend them to people wanting to put a new tree in at their homes. One thing they can’t handle? Aggressive bark stripping by our campus squirrels. The squirrels like those trees in particular because they have “Goldilocks” bark that is neither too hard nor too soft. They nibble for a number of reasons…this tree produces a sugary sap that they appreciate, there is some thought that it may be territorial marking, and importantly their teeth continually grow and must be ground down. And our squirrels are – ahem – somewhat portly from people feeding them everything from bread to peanuts. That food is soft relative to their normal diet and it makes them need to knaw even more that they typically would. If it were just a little munching here and there the trees would shake it off. We have so many squirrels, though, and they follow each other. If one does it, others will too. All those wounds not only disrupt the vascular system of the tree, they are entry points for pathogens particularly fungus. Over time branches are girdled and fail, cankers develop all over, destructive insects move in, and eventually the trees will die.
There’s nothing really to be done to stop or prevent the squirrel damage that is the genesis of the decline spiral for the trees. It would be great if there was a repellant or something that made the tree taste bad, or a hawk or owl took up residence nearby, or someone quite bored who hung around there all the time with a pellet gun and pinged them in the butt every time they got caught in the pistaches until they stopped. In the absence of that, we just plan to keep removing dead bits until there’s basically nothing left. One of the three will probably come out this winter and we will just keep limping the others along for as long as we can.
Well, this is a bummer but remember, once upon a time there used to be big fat palm trees in the general area:
Bonus: Whenever those pistachio leaves turn yellow I always remember this picture from the winter 2004 issue of the Sallyport.