I planted a few raspberry canes this spring, I had picked them up from the local garden centre, and when I planted them, they looked great.

However, about a week or two ago I noticed that one cane's leaves were quite noticeably yellow and brown and dried out at the edges. I took a look for insects or any insect damage, but the leaves themselves appeared to be intact. I thought maybe a lack of water, but the soil was nice and moist. I left the suspect cane in for a few days longer, hoping it would look better with time, but it didn't so I pulled it out on Friday. Now, the cane that is immediately beside the cane is showing these same symptoms -- help!! What could this be??