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Thursday - October 22, 2015

From: Houston, TX
Region: Select Region
Topic: Herbs/Forbs
Title: Is Iva Angustifolia Salt Tolerant?
Answered by: Anne Van Nest


I was wondering about the salt tolerance of narrow-leaf sumpweed (Iva angustifolia). It is the predominant species on a disturbed site in Haynesville, LA where brine contamination is in question. Until we can sample the soil, I was wondering what this plant could tell us about the environment.


The Louisiana Department of Wildlife and Fisheries has a good factsheet online about the Natural Communities of Louisiana and lists Iva angustifolia as a halophytic (salt-tolerant) native plant in the interior salt flat community.

The Texas AgriLife Extension service lists Iva angustifolia in their Plants of Texas Rangelands website. They write ... Marshelder is a native, warm-season annual that is also commonly named "narrowleaf sumpweed." A member of the Sunflower family, it is characterized by its leaf-like bracts in the flowering stem. Marshelder is very drought tolerant.

This plant germinates in the early spring in February or March and is mostly vegetative, with long, narrow leaves. The flowers, which resemble those of the ragweed group, are inconspicuous. It flowers in late summer and fall. Marshelder occurs on seepy areas or those that may hold some water in the spring, especially along the edges of creeks and ponds



From the Image Gallery

Narrowleaf marshelder
Iva angustifolia

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