Oh, how time flies… I feel like most plants have finally fully leafed out and it’s almost June already. Unsurprisingly, May’s weather has been hot, cold, wet, and dry which makes for some interesting situations in the urban landscape. Below are some highlights of what’s been going on:

• That nasty -30-degree weather that showed up for 2 days or so before Christmas is having lasting effects. Evergreens, both broadleaf and conifers, took a hit. The tips of arborvitae got burnt, larger stems of crape myrtles died back, laurel shrubs were killed, and southern magnolias aren’t too happy. That’s the risk we take by planting those types of species in our climate.
• Just when it seemed a bit dry for May, it rained, and it didn’t stop for some time. Along with the excess moisture came fungus! Foliar fungal diseases are very apparent in many landscapes. Most commonly, these diseases may cause leaves to shed early in the season.
  • Apple scab on crabapple
  • Cedar-apple rust on juniper, hawthorn, crabapple, and pear
  • Bacterial leaf scorch on pear and crabapple
  • Anthracnose on ash, oak, and maple
• What’s happening to all the sycamores?! Just when sycamores began to leaf out, their leaves quickly cowered up and began littering the ground below. Unlike anthracnose on ash, oak, maple, and others, sycamore anthracnose is a bit different (and can be more serious). This disease produces cankers, or sunken lesions, in the twigs which may distort future growth and/or cause dieback. Annual defoliation from this disease can prove harmful and preventative treatment on specimens may be worth the consideration.
• Bagworms should be emerging relatively soon, so keep an eye on your arborvitae and other potential hosts!

Weather is a huge driver for plant performance. We’ve started the season off wet but don’t be surprised if it gets HOT and dry, which will trigger a whole separate set of issues down the road.