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In-depth plant profiles, disease identification, and pest management for Western Washington.
Bronze birch borer kills stressed birches from the canopy down, and understanding the delay between drought stress and visible damage is the key to saving trees that can still be saved. GDD timing, resistance chemistry, treatment thresholds, and species substitution for the Puget Sound lowlands.
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You've probably seen a mulch volcano and helped create one. Here's what that pile is doing to your tree, and how to mulch correctly for the soil under your feet.
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Copper fungicide is one of the few organic materials that works against both fungal and bacterial pathogens. Here is what it controls in the Puget Sound landscape, when to spray it, and the real constraints you need to respect.
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The most effective pest and disease treatments happen when your trees look dead. Here is what to spray, when to spray it, and why the timing window matters.
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You already have one. That is the starting point for most conversations about Callery pear (Pyrus calleryana) in Western Washington. It sits in your front yard, lines your street, anchors the...
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A native evergreen that screens, fixes nitrogen, and asks for almost nothing in return. Privacy, wind protection, and soil improvement in one fast-growing package.
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The tallest native hardwood in Western Washington, and why you need to understand it before you decide to keep or remove one.
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Washington's only native oak species carries the weight of an entire ecosystem. Learn how to recognize, protect, and restore Quercus garryana on your property and in your region.
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Armored and soft scale insects look similar on bark but require completely different management. Learn the field test that separates them, when crawlers emerge by GDD, and why ant exclusion may be the most effective single intervention.
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Why Western Washington's wet winters create perfect conditions for Phytophthora, and how to protect your landscape.
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Learn the difference between cosmetic leaf spot anthracnose and destructive dogwood canker disease. Regional strategy for the Pacific Northwest.
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Aphids are everywhere in our region's gardens. The best response is usually no response at all. Here is how to tell when that changes.
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How to prune young trees for storm resistance, structural integrity, and decades of trouble-free growth in Western Washington.
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Walk through any Western Washington neighborhood in early spring, and you'll spot the evidence: trees that look like they've been given blunt haircuts, their canopies reduced to stumpy branches with...
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Two years ago, your contractor promised you the big Douglas-fir would be fine. The tree had shaded your house for forty years, and the remodel was necessary. You watched them work around it. No major...
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You step outside the morning after a cold snap in January and stop cold. A vertical crack runs down the trunk of your maple or cherry, splitting the bark from somewhere high up and descending several...
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You walk into your local nursery in the Puget Sound region and find a 15-gallon Douglas-fir or Japanese maple. The tag reads "ready to plant." You load it into your truck, dig a hole in your yard,...
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You can eliminate most tree problems before you plant a single sapling. Match the tree to the site, and you won't spend the next twenty years fighting with dead branches, structural failure, or roots...
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National spring lawn advice assumes winter dormancy. Puget Sound lawns skip that step. Here is what to do about moss, compaction, and clay soil damage instead.
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Your grape variety determines your pruning method. Learn spur pruning vs. cane pruning, wet-climate timing to prevent trunk disease, and a variety-by-variety reference table for the Puget Sound lowlands.
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Clematis confusion starts the moment you bring one home. You've got a beautiful vine covered in flowers, and then someone tells you to prune it. Cut it back hard? Light prune? Wait until next year?...
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You plant a tree in October. The rain starts in November, and you think you're done. The soil stays wet through winter and spring. By June, you've forgotten about that tree entirely. Then July hits,...
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Growing degree days are the accumulated heat units that drive every biological event in your landscape. HortGuide uses base 32°F for maritime climates. This guide explains the calculation, the conversion methodology, source data, and how to read the season tracker.
Read more →One p or two? The abbreviations sp. and spp. after a genus name mean different things. Learn the distinction, the Latin behind it, and how to read them on nursery tags, lab reports, and pesticide labels.
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Every nursery tag carries four layers of naming. One of them predicts how the plant will perform in your yard. Learn to decode species, cultivar, trade name, and patent so you buy exactly what you intend.
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If you track four numbers through the year, you can predict when your fruit trees will break dormancy, when the soil is warm enough to plant, whether your season is running ahead or behind, and how much solar energy your landscape is actually receiving.
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