Sunday, September 19, 2010

Bright Red Fall Folliage: Itea virginica

For bright red fall foliage, Victoria recommends Itea shrubs –and to avoid the invasive euonymus (burning bush). Itea, as you can see, produces ravishing red fall color.

"Little Henry' Itea virginica.

'Henry's Garnet' Itea virginica.

Why should you avoid planting 'burning bush'?: "The invasive euonymus (burning bush) was introduced into the USA from northeastern Asia about 1860 and the bright red fall foliage makes this shrub a popular ornamental; burning-bush planted near woodlands, mature second-growth forests, and pastures can be a problem. It has escaped from cultivation in the Northeast and Midwest, notably in Connecticut, New York, Virginia, Pennsylvania, and Illinois.

The earliest evidence of naturalized populations of winged euonymus in eastern Pennsylvania dates from the 1960s. Today it is found with increasing frequency in moist forests throughout the eastern United States.

Winged euonymus is a threat to mature forests and successional fields and woodlands because it out-competes native species. It is adaptable to various environmental conditions although it generally does not do well in very dry areas. It grows well in a variety of soil types and pH levels, has no serious pest problems in North America, and most importantly of all, is tolerant of full shade. It has invaded moist forested sites creating dense thickets that can shade out native herbs and shrubs.

Seed production is prodigious; many germinate where they fall close to the mother plant creating dense beds of seedlings. Others are spread by birds that are attracted to the seeds by their nutritious, fleshy, red covering (aril). Seeds dispersed this way germinate easily and spread the infestation rapidly. Wide usage of this a popular landscape ornamental increases the probability that more will escape from cultivation.

Winged euonymus should not be planted anywhere near native forest stands because of its invasiveness and prolific seed production.

The following native shrubs are suggested as alternatives:

winterberry holly (Ilex verticillata),
red chokeberry (Aronia arbutifolia),

Virginia sweetspire (Itea virginica)
arrow-wood (Viburnum recognitum or V. dentatum),
blackhaw (Viburnum prunifolium),
gray dogwood (Cornus racemosa),
kinnikinik (Cornus amomum),
ninebark (Physocarpus opulifolius),
witch-hazel (Hamamelis virginiana),
bayberry (Myrica pensylvanica)."

-SOURCE: The following information on this species is taken from the Delaware River Invasive Plant Partnership, Invasive Plant Fact Sheets.

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