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Planting under oak tree

18 years ago

Hello fellow gardeners,

I am not new to gardening, but I am new to Oregon, and new to my particular garden site. Just bought my first home & want to do this right. I could really use some help. My yard is almost entirely within the canopy of a very magnificent old oak tree. I have been told by a landscaper and a couple of arborists that itÂs a pin oak, a scarlet oak, a white oak, and on & on. From my own research I think itÂs probably a northern red oak, quite common in Portland I hear. I called the University of Oregon Master Gardeners line in Clackamas County for advice and was told that oak trees are allelopathic in nature and that it will be a struggle to plant anything beneath it. I asked for suggestions on compatible plants and he just pretty much said nothing will do well. I have never felt so shot down or discouraged in my gardening life. I have heard of walnut trees being toxic to other plants but not oaks. From what I could learn on the internet oaks give off a chemical substance called coumarin that discourages herbs and grasses. Does this mean herbaceous perennials? I would love to hear from any others who garden under oak trees in Portland. My understanding of allelopathy is that itÂs a way that a plant "protects" it territory, meaning making it difficult for other plants to compete for nutrients by exuding a chemical through roots and fallen leaves... There has got to be a way around this. I was hoping to create a dry shade garden that encouraged bird and butterfly habitat. Do you think I should post this in any other forums? (I am also new to the gardening forums). Are all Master Gardeners that darn mean? Thanks for your help. Oh! By the way Master Gardener also told me not use the fallen oak leaves in my compost. This advice seems totally bizarre to me, but then IÂm from California so IÂm more than willing to look stupid. Sorry this is so long.

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