I have a eucalyptus tree about 6-7 years old. This summer, most of the leaves have turned reddish, with very few silvery green left. Is this a natural process or is it dying?
Is My Eucalyptus Dying?
I don't know which variety of eucalyptus you have, but it doesn't sound like a thing it should be doing, especially if you've had it several years and this never happened before. Try to find out if there is live wood on the tree - scrape the bark with a dull knife to see if it's green under the surface; or bend small branches, which will be flexible if alive, and snap apart all brown inside if dead. If only part is dead, cut the branches back to live wood, and investigate to see if you can improve the general care, of find any disease or pests. These articles should be helpful: https://www.gardeningknowhow.com/ornamental/trees/eucalyptus/tips-growing-eucalyptus.htm