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Home , Allium amplectens, Brodiaea, Camassia, Camassia leichtlinii, Camassia quamash, Toxicoscordion venenosum

NATIVE AND ECOLOGICAL RESTORATION IN THE -OAK HABITATS OF THE -PUGET TROUGH- BASIN ECOREGION

Ed Alverson 27 October 2015

Photo: Katie Mackendrick Overview of Presentation

• Definitions of bulbs, , and other geophytes • Bulbs in the WPG prairie flora • Monocot families with bulbs • Bulbs and prairie remnant management • Ecological functions of bulbs • reproduction and growth • Bulbs in prairie restoration, challenges and case studies Bulbs, Corms and other Geophytes

Geophyte: According to the Raunkiær system, a of Cryptophyte (resting bud below ground) with roots or shoots that are modified as a storage organ

Bulb: has basal plate with scales that are modified leaves : a swollen underground stem, with basal plate but lacking scales Tuber: fleshy underground stem with no basal plate Rhizome: underground stem that sends out roots and shoots from its nodes Bulbs in the WPG prairie flora

• Bulbs are 28 of 556 High or • acuminatum Moderate Fidelity taxa in the • Allium amplectens in the WPG prairie flora (5%) • coronaria ssp. coronaria • Only 11 taxa from 8 genera are • leichtlinii ssp. suksdorfii distributed throughout the WPG ecoregion • ssp. maxima • congestum • Yet, they are a visually important part of the native • Erythronium oregonum ssp. oregonum flora at most high quality • Fritillaria affinis var. affinis remnant sites. • venenosum var. venenosum • grandiflora var. howellii • Toxicoscordion “true lilies”: venenosum E. oregonum ssp. leucandrum

Calochortus tolmiei

Fritillaria affinis

Lilium columbianum Erythronium oregonum ssp. oregonum “false lilies”:

Dichelostemma congestum

Brodiaea elegans ssp. hooveri

Allium amplectens ssp. suksdorfii Triteleia hyacinthina Functional Roles of Bulbs

• for vertebrate and invertebrate herbivores (both foliage and bulbs), including endangered • Source of nectar and pollen for a of pollinators, including endangered species • Important food source for native People (7000 year old camas ovens) • Popular native ornamentals Bulb reproduction and growth

• Active growth during spring, dying back and going doermant in summer to avoid drought • generally require cold stratification to germinate • Seedlings and young have a single grass-like leaf • Typically only flowering individuals produce 2 or more leaves Bulbs and Prairie Remnant Management

• Fire and mowing have both been found to increase Camassia abundance in replicated experiments (Macdougall and Turkington, Restoration Ecology, 2007; Nuckols et al., Northwest Science, 2011) • Probable mechanism is release from suppression due to grass thatch reduction • Effect is generally short-lived unless applied repeatedly • Effect may vary depending upon soil characteristics that affect grass vigor (soil depth, nutrient levels, etc.) Bulbs in Prairie Restoration (“Reconstruction”): Challenges

• Difficult to wild collect in large quantity • Seed grow-out in nurseries is slow process • Young seedlings are small and easily out-competed by more vigorous natives • Planting individual bulbs is expensive and unlikely to achieve desired abundance Bulbs in Prairie Restoration: Case Studies:

Eastern Gateway Wetland Restoration, West Eugene Wetlands • Site prep by removing previously placed fill material • Seeded in Fall 1993, including ca 40 lbs of hand-collected Camassia • Hydrology over parts of site too wet for Camassia • 20+ Years later, Camassia is flowering in restoration area in moderate quantity • Both Camasia quamash and C. leichtlinii present Bulbs in Prairie Restoration: Case Studies:

Urban landscape, Eugene • Site prep with black plastic and broad spectrum herbicides • Year 1: bulbs only seeded in Fall 2011, including Camassia and Brodiaea • Year 2: Festuca roemeri and Carex seeded • Year 3: other grasses and broadleaf forbs seeded • Year 4: Camassia and Brodiaea flowering in quantity

2015 Questions?