Hi All, This flowering crabapple tree was planted in 2018 and had been doing very well up until this year. It is in a spot where it gets a lot of sunlight. I brought in some amending soil and mulch in early March and other than that there has been no changes to our garden. Right after bloom the tree dropped about half of it's leaves. I peeled back the bark on the affected branches and they appear to still be healthy? I'm wondering if this is a fungus or pest issue or has this to do with drainage? If it is a fungus, what should treatment be? Thanks in advance! Regards, Jonathan
Was the soil level with the yard before, and now you've built the bed up? Do you recall what cultivar of crabapple it is?
This looks like it could be Fire Blight; for a detailed description, see Fire Blight of Apple and Pear - Province of British Columbia. I get Fire Blight on the blossoms of my Oriental pear if i don't spray with copper at blossom time. This year it seems to have killed all of the blossoms because it rained so frequently during blooming that I couldn't spray then.
Hi Daniel, The bed was originally 12 inches when planted. We had a fair amount of soil loss over the last few years so I brought in about 2 inches of top soil and 2 inches of mulch. At the time I brought in the soil the trees roots were exposed....I see now that you should be careful not to pile up too much soil/mulch around the trees. I also see Vitog's comment above....that would not be good! Thoughts on a path forward? Thanks so much to both of you
Hi, yes, reading this: ENH-555/ST396: Malus x 'Spring Snow': 'Spring Snow' Crabapple , it sounds like this cultivar is particularly susceptible to fireblight. As @vitog mentioned, copper sprays at the prescribed time will help. There's not much to be done this year, but usually a healthy tree can handle one setback year.
Fire blight is a phenomenon needing summer-like temperatures in spring making it unlikely in North Vancouver most of the time - notice the Province of British Columbia article linked to above talks about it being a problem in the apple and pear producing regions of the province. In other words east of the mountains, same as here in Washington. So unless that hot spell last June was early enough and otherwise suitable for your tree to have fire blight develop look up false fire blight (Pseudomonas) to see if that fits.