Reference Data · Western Washington

The Library

Searchable directories of plants, diseases, pests, beneficial organisms, and soils - with host associations, susceptibility data, and management references built from regional extension research.

2,619 profiles indexed · Type a name, genus, or keyword

2,619
Total Profiles
21,042
Host Associations
562
PNW Natives
9
Soil Series

Recently Researched

Profile updates driven by guide research and source monitoring

Browse library →
Source Update

Boxwood Blight profile updated with new infection conditions, spread mechanism, and cultural management practices from OSU Extension EM 9586 'Boxwood blight uncovered:... and OSU Extension EM 9586 —...

OSU Extension EM 9586 'Boxwood blight uncovered:... and OSU Extension EM 9586 —...

Guide Research

Asian Pear enriched with flower description, etymology, bark, and 6 more areas from Field observation, Issaquah WA, 2026-03-21, Field observation, Pyrus pyrifolia 'Chojuro',..., Hartman's Asian pear pollination chart (Western..., and 23 other sources.

Field observation, Issaquah WA, 2026-03-21, Field observation, Pyrus pyrifolia 'Chojuro',..., Hartman's Asian pear pollination chart (Western..., and 23 other sources

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Source Update

Cottony cushion scale and White Pine Blister Rust profiles updated with host range, infection conditions, vulnerability timing, and 6 more areas from UC IPM Pest Note 7410: Cottony Cushion Scale and UC IPM Pest Note 7602: White Pine Blister Rust.

UC IPM Pest Note 7410: Cottony Cushion Scale and UC IPM Pest Note 7602: White Pine Blister Rust

Source Update
Scab + 7 profiles

Scab, Alder Canker and Stem Diseases, Rose Mosaic, and 5 more profiles updated with vulnerability timing, diagnostic features, identification, and 14 more areas from OSU Extension - How to manage apple scab during..., OSU Extension - SLF forecast model impact page, OSU Extension - Vaughn Walton, OSU Extension..., and 4 other sources.

OSU Extension - How to manage apple scab during..., OSU Extension - SLF forecast model impact page, OSU Extension - Vaughn Walton, OSU Extension..., and 4 other sources

Guide Research
Leaf Spot + 5 profiles

6 disease profiles enriched with regional notes and chemical control options from Alabama Extension, Morton Arboretum, NC State Extension, and 6 other sources.

Alabama Extension, Morton Arboretum, NC State Extension, and 6 other sources

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Guide Research

Slug enriched with identification details, host range, lifecycle stages, and 5 more areas from Cornell Biocontrol, Cornell IPM, Edwards et al. 2009, and 14 other sources.

Cornell Biocontrol, Cornell IPM, Edwards et al. 2009, and 14 other sources

Guide Research

Garlic Mustard enriched with regional notes.

Guide Research

Powdery Mildew enriched with causal agent identification, causal agent by host, host range, and 2 more areas from Cornell PDDC, PNW Plant Disease Management Handbook, UC Davis IPM, and 3 other sources.

Cornell PDDC, PNW Plant Disease Management Handbook, UC Davis IPM, and 3 other sources

Source Update

Scab profile updated with new regional notes from OSU Extension: 'How to manage apple scab during...

OSU Extension: 'How to manage apple scab during...

Guide Research

Iron Chlorosis enriched with trigger threshold (pH >7 VERIFY flag) and regional notes from NC State Extension Gardener Handbook Ch 1, UC IPM, and UC IPM pH Problems.

NC State Extension Gardener Handbook Ch 1, UC IPM, and UC IPM pH Problems

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Guide Research

Ground Beetles (Carabidae) enriched with target pest species, pest profile links, native status, and 4 more areas from Ahn et al. 2012 (ZooKeys 147:497-543), Ahn et al. 2012 on Nebria brevicollis establishment, OSU EM 9301 (Reich et al. 2021), and 5 other sources.

Ahn et al. 2012 (ZooKeys 147:497-543), Ahn et al. 2012 on Nebria brevicollis establishment, OSU EM 9301 (Reich et al. 2021), and 5 other sources

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Guide Research

10 plant profiles enriched with regional notes, cultivar data, soil drainage preferences, and 9 more areas from Briggs Nursery, USPP database, OSU Landscape Plants, Pacific Horticulture, Pacific Horticulture community planting framework, and 13 other sources.

Briggs Nursery, USPP database, OSU Landscape Plants, Pacific Horticulture, Pacific Horticulture community planting framework, and 13 other sources

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Most Connected Plants

Species with the highest number of documented disease and pest associations in the library. More connections means more to watch for - and more management decisions per season.

Deepest Cultivar Data

All plants →

Profiles with the most cultivar-specific resistance and performance data - useful for making informed variety selections.

Active Project

Data Enrichment in Progress

This library grows through continuous data collection and verification. Profiles start with identity and host associations, then deepen with site data, phenological timing, cultivar performance, and regional management notes. Each dimension is sourced from extension research and field observation.

Data Maturity Tiers

Every profile carries a maturity tier reflecting how much verification it's received. You'll see this as a four-segment meter on each profile page.

Baseline

Bulk-imported from authoritative databases. Accurate identity, no human review yet.

Structured

Synthesized from multiple sources. Conflicts surfaced, data organized coherently.

Expert-Reviewed

Reviewed by a credentialed arborist. Regional context verified for local use.

Field-Verified

Expert-reviewed plus validated with original field observations from this region.

How maturity tiers work →

Profile data drawn from 40+ registered sources including university extension databases, federal plant inventories, and original field observations. Full methodology →