I planted 26 emerald arborvitae trees this summer. All but three are looking good. On each of those three, one of the shoots died. If I cut that part out, will the trees fill in?
Yes, it will if those cedars are healthy. You should investigate to find out why the shoots died. Some possible causes with freshly planted cedars are:
- inadequate watering; new plants need a lot of water the first season
- too much watering: are they planted in a very wet area?
- spider mites or scale or leaf miner are common problems. See here
- physical damage during planting, deer
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