Not fun, guy: fungi, other ailments put Washington madrone trees in decade-long funk

Five of the homes we’ve lived in here in Kitsap County have had a madrone Arbutus menziesii in the garden. It may be my most favorite of all the trees. For more than 10 years, though, the madrones in our Washington State neighborhoods have been suffering from a host of maladies. Some are fungal in nature and others involve root rots called phytophthoras. Canker can also attack the tree.

Five of the homes we’ve lived in here in Kitsap County have had a madrone Arbutus menziesii in the garden. It may be my most favorite of all the trees.

This magnificent tree provides shelter for birds and insects, along with food and nectar, with its lily-of-the valley, pieris-blossom-like flowers. Its peeling bark and multicolored trunk and branches lend an ever-changing pattern of shadow and light. The evergreen leaves are a glossy very dark green with a much lighter underside often described as glaucus or white. Red-orange berries provide food for creatures including humans who in the past would make jellies out of the fruit. Arbutus menziesii has several medicinal uses and native peoples used it for a multitude of purposes.

For more than 10 years, though, the madrones in our Washington State neighborhoods have been suffering from a host of maladies. Some are fungal in nature and others involve root rots called phytophthoras. Canker can also attack the tree. More than 21 fungi have been identified as using madrone as their host plant. Some researches say there are more than 39 fungi that invade madrone.

Arbutus menziesii can grow 50 to 100 feet in the wild and in our developed gardens will grow to at least 20 to 50 feet. The trees lean out on the edge of forests, hold banks together and love sun. They’re native to California, Oregon and British Columbia. Flowers appear in March through May, depending on the region. Berries follow next and each year the tree sheds — first the flowers, then the berries and what seems like hundreds of leaves. Birds eat the fruit and deposit madrone seeds all over our gardens where they sprout up quite easily if the soil is to their liking. Their growing region is from shorelines up to as high as 5,000 feet above sea level.

Over the past several years we’ve received quite a few calls from local gardeners about the madrones in their gardens encountering problems. Several articles have been written citing property development as one of the causes. Madrones do not like to have their roots and soil structure disturbed. Marianne Elliot from University of Washington College of Forest Resources has studied madrones extensively and has quantified and examined the diseases, fungi and cankers that attack madrones.

The fungi that is the most noticeable is exhibited by spots on the leaves, which over time completely cover much of the foliage, turning it a charcoal black. Some trees die from this condition. Others will lose limbs to it, yet survive. The best way to handle this condition is to rake up and dispose of the foliage on the ground. Prune off the dead branches. If the madrone dies completely, cut it down. It will often resprout sending up new shoots from the base of the stump. The new growth often escapes the fungal disease for many years until the tree begins to mature again into a towering height. New seedlings often escape the fungi too.

If you’re fortunate enough to have a healthy Arbutus menziesii in your garden or neighborhood enjoy it as long as you can. Remember too, that many species will change over time to overcome the diseases that are affecting their predecessors. Let’s all hope for the best for our native madrones.

For more information visit these Web sites:

• seattletimes.nwsource.com/html/outdoors/2002049584_nwwmadrona30.html

• www.rainyside.com/features/plant_gallery/nativeplants/Arbutus_menziesii.html

• www.ubcbotanicalgarden.org/potd/2006/09/arbutus_menziesii.php

• www.ubcbotanicalgarden.org/potd/2006/09/arbutus_menziesii.php

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