Oversized yew

(Question)

I have a yew in front of my house that was overgrown when we bought the house, 18 years ago. We have tried to keep it under control (we keep it ’rounded’ ) but it is too large for the space and we now believe it is having an effect on drainage and causing water problems in our basement.
We would like to remove the tree/bush and replace it with another evergreen bush. We think cutting the tree down is easy, but how do we dispose of the enormous root system that must be underground, to make room for a new plant.
We would like to do this ourselves. Any suggestions would be appreciated. Also any suggestions for a replacement – south facing – space is beside a 4 foot stone wall( steps to front door) and would be in front the house (stone) underneath the front window (5 feet up) thanks in advance.

(Answer)

Thank you for your yew Q: I am doing the math, and conservatively assuming that your yew was maybe 5 years old when you took over ownership, you now have a yew that is over 2 decades mature. Yes, yew “shrubs” can, over time, develop into yew trees.

The yew is a member of the coniferous Taxaceaea Family, native to Japan, Korea and Manchuria. In the Ontario region, they have always been much beloved for their colourful, frosted red fleshy arils (seed cups) that attract winter feeding birds, such as cardinals, juncos  and grosbeaks. Also, they typically thrive well with regular pruning and shaping. Yet, they are strong enough growers, that, if not held in check for a significant period of time, could become heavy eaters with historically overbearing root systems.

Just for the record, you might wish to consider pruning back your yew to several main branches, improving the soil culture with mulch/fertilizer, and water, and wait and see what new growth appears this season, and continue to maintain. You mention that you’ve kept the yew “rounded”, but I wonder, with respect for your efforts, if you have actually been aggressive enough. If you feel you have the patience for another year, you could choose to treat your yew to one more spring pruning, this time more vigorously — with a design for new growth in mind.

Otherwise, remove the existing yew entirely, both above and below the ground: much heavy lifting required. I’ve never attempted the removal of a yew root system, but I have removed a small tree. At the time, I was given the best piece of advice for the whole operation — start soaking the ground around the trunk several days in advance of the “big dig”, not to make it mucky, but so that the water has a chance to really loosen the soil 18″- 24″ below the ground. In the meantime, use a lopper to cut off all the branches, leaving 8″- 12″ above ground. Then dig (with a long-handled shovel, to save your back) around those remaining branches, about 3′ deep. Next, with a pruning saw, trim those branches as close to the main trunk as possible, and also use the lopper to sever all the roots you can find. The idea is to entirely discourage the yew roots from self-propagating underground. Depending on the diameter of the trunk and root system you find, you may need to finally take a chain saw to cut out as much of the remaining root material as possible. While you’re saying sayonara to your yew, don’t forget to save the resulting mulch for your new planting.

During your break times, you can mull over your choices for replacement bushes. Aesthetically, what kind of  “look” would you prefer? For example, some coniferous pines can lend an exotic, formal appearance, such as the dwarf  Pinus mugo, mugo pine, which could be planted as one specimen, or, say, a three-some. Dwarf mugo will grow to 4’x4′. On the other hand, you may wish something less formal, and colourful, such as Cornus kousa, the deciduous Kousa dogwood shrub, loved for its white-bracted flowers, red fruit, interesting bark, as well as  foliage that turns red and purple in the fall. And, of course, it’s always useful, and fun, to go window-shopping at nurseries, or the Toronto Botanical Garden, and look at actual specimens in situ, to help visualize your options.

In closing, the TMG has an excellent Guide to offer you with advice on planting both conifers and deciduous: https://www.torontomastergardeners.ca/index.php/factsheet/planting-a-tree-a-toronto-master-gardeners-guide/

Also, information regarding some of the tools you may require:  https://www.torontomastergardeners.ca/index.php/askagardener/pruner/

And here is one of our TMG Guides for pruning — great reading: https://www.torontomastergardeners.ca/index.php/factsheet/evergreens-suitable-for-hedging-a-toronto-master-gardeners-guide/

Thank you for writing, and all the very best with your spring project !