Tamarisk (also known as salt cedar) is a deciduous shrub or small tree from Eurasia; thus it loses its leaves each year, making it difficult to observe during the period when it has no leaves. Tamarisk has a deep, extensive root system.

During successive seasonal rain events mature Tam can be pushed down and buried by new deposits, this allows new plants to regrow along the entire buried plant stem. We have seen them do this through 6’ of newly deposited sand and gravel and over 50’ of river length .

Flowering branches are mostly primary or secondary branches. Each plant can produce as many as 500,000 seeds annually, and can produce seeds throughout the growing season. High stress induced by fire, drought, herbicides, or cutting can increase flowering and seed production.

The seeds are dispersed by wind and water. Seeds are small with a tuft of hair attached to one end enabling them to float long distances by wind and water. Seeds are short-lived and do not form a persistent seed bank.

However, they can germinate within 24 hours of dispersal, sometimes while still floating on water. Seeds produced during the summer remain viable for 24 to 45 days. Winter longevity is approximately 130 days.

Seed mortality is generally due to desiccation. If seeds are not germinated during the summer that they are dispersed, almost none germinate the following spring.

Tamarisk trees on floodplains can be difficult to kill, requiring several treatments.

A single adult Tamarisk can drink up and flash off over 200 gallons of water a day through evapotranspiration. When multiplied by the millions of tamarisk in the South Western United States it is easy to see how some of our water challenges might be relieved by removing these invasive plants.

The root systems of trees on floodplains are more extensively developed near the ground surface, due to repeated scouring and removal of limbs by floods, and can send up shoots where none existed at the time of initial treatment.

Because difficulty in accessing and the rugged terrain, some of these areas are rarely visited. In the more popular and drainages with trails we may be the one of a handful of groups to enter all year. In the more rugged drainages we may be the only group to enter in a century.

Santa Ynez River

Our Tamarisk eradication project in the Santa Ynez River is intended to restore 170 miles of riparian habitat in the upper reaches of the watershed above Gibraltar Dam. Working in the headwaters of the river also benefits downstream riparian habitats outside of the Forest. Channel Islands Restoration will hike 170 miles of the upper Santa Ynez River and fourteen tributary streams and canyons upstream of Gibraltar Dam.

The streams that we will survey include some of the most beautiful and vibrant streams in Santa Barbara County including Indian Creek, Mono Creek, Pie Canyon, Alamar Canyon, Roblar Canyon, Agua Caliente Creek, Horse Canyon, Rose Canyon, Diablo Canyon, North Fork of Juncal Creek, Juncal Canyon, Alder Creek, Fox Creek, and Blue Canyon.