The Week in Horticulture

     I have spent most of this week at the Mid-Atlantic Horticulture Short Course. I serve on the board of its sponsoring organization, and I have attended this annual event for decades now. It has always been a welcome diversion during the cold part of the year, as I look forward to being introduced to new plants, learning from great designers, and networking with my fellow green people, though others have referred to it as a CEU and certification farm. I found this year's conference somewhat somber in tone, as it seemed to me that many of the classes (at least the ones I took) concerned horticulture's response to a changing world, especially as it relates to climate. The keynote speaker was Michele Covi of Old Dominion University, and she set the tone with her talk on sea level rise and its affect on southeastern Virginia, after New Orleans, this country's most at-risk metropolitan area. I am sure I have mentioned that fact before, so pardon me for repetition, but it weighs on my mind constantly.

     One of the most interesting classes I took was on a community-based program in Richmond that used a great deal of science, technology, and willing teenagers to measure the phenomenon of urban heat islands. They went all over the city last summer to measure ambient temperatures on a very hot July day. Comparing the collected data with maps of the city's tree cover, it was clear that the cooler parts of the city also had more trees, while the hottest areas were full of asphalt. They overlaid these combined maps with income levels, as well as the number of ambulance calls during heat waves, and the way the patterns lined up was eerily perfect. Another climate-centric talk I went to showed, among other things, how new computer programs predict the effects of a warming planet on native trees of Virginia, and where these species might have to migrate to to escape the heat, this as other more heat-tolerant trees could possible seize the void. This same talk framed everything in either of two scenarios, one where we do nothing to abate climate change, and another where we do what we can and hope for the best. Even under the best circumstances, the news is not good. For some time now I have been convinced that there is really nothing we can do to stop climate change, we can only manage its effects. Even if we slam on the brakes right now, the best we can do is to hope for a slow down, not a complete stop.

     I also attended talks on introduced pests, including emerald ash borers, crapemyrtle bark scale, and ambrosia beetles. These are just a few of the threats to our natural and man-made landscapes resulting from a more connected world. The best news I got from these talks is that two species of our own lady beetles have now put crapemyrtle bark scale on their diets, especially important here in Norfolk, where 50% of all street trees are crapemyrtles. Technology played a role in several of the talks including using drones in forestry, sonic tomogaphy, and resistorgraphs. The latter are two non-invasive ways access tree health. There were also classes on phytoremediation, creationg bio-retention ponds, using IPM and biological pest control, and yes, there were pictures of pretty flowers too.