Tag: invasive species

Siberian Elm

Siberian elm (Ulmus pumila)

Siberian elm (Ulmus pumila) is a locally widespread tree common to the southwestern US. It is a mid-size tree that can reach 70 feet tall.  At Watson Woods Riparian Preserve this tree out-competes native cottonwoods, willows, ash, boxelder, and walnuts to the extent that Prescott Creeks has listed it as a Priority 1 species on

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Dalmation Toadflax (Linaria dalmatica)

Dalmation toadflax is a wide spread invasive. The extent of it’s spread can be seen in this map from the Natural Resources Conservation Service. Originally brought to North America from the Mediterranean region of Europe as an ornamental, Dalmatian toadflax is currently found in at least 34 states in the U.S. and most of the

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Diffuse Knapweed (Centaurea diffusa)

Diffuse knapweed is an annual or biennial plant , generally growing to between 10 and 60 cm in height. It has a highly branched stem and a large taproot , as well as a basal rosette of leaves with smaller leaves alternating on the upright stems. Flowers are usually white or pink and grow out

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Russian Knapweed (Acroptilon repens)

Like other creeping perennials, the key to Russian knapweed control is to stress the weed and cause it to expend nutrient stores in its root system. An integrated management plan should be developed that places continual stress on the weed. Currently, the best management plan includes cultural control combined with mechanical and/or chemical control techniques.

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Russian Olive (Eleaganus angustifolia)

Acc ording to the National Park Service: Russian-olive is a small, usually thorny shrub or small tree that can grow to 30 feet in height. Its stems, buds, and leaves have a dense covering of silvery to rusty scales. Leaves are egg or lance-shaped, smooth margined, and alternate along the stem. At three years of

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Spotted Knapweed (Centaurea maculosa)

This is often a favorite to hate in the central Arizona highlands. Knapweed is a pioneer species found in recently disturbed sites or openings. Once it has been established at a disturbed site, it continues to spread into the surrounding habitat. This species outcompetes natives through at least three methods: A tap root that sucks up water

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Malta Starthistle (Centaurea melitensis)

Malta starthistle (synonyms: Napa starthistle, tocalote) is an annual invasive weed with foliage and winged stems that are grayish to green in color. Its thistle-like appearance is similar to yellow starthistle (C. solstitialis), but Malta starthistle is distinguished by smaller yellow flowers and longer seedpods that are armed with relatively short spines (less than 1/2

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Sweet Resinbush (Euryops subcarnosus)

From the CA Extension offices: Sweet resinbush (Euryops subcarnosus) is an exotic species from South Africa that was introduced in Arizona during the 1930’s.It was brought here in hopes that it would provide forage for livestock and aid in slowing soil erosion. Potted plants were sent to Civilian Conservation Corps camps in 1935 where they

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Scotch Thistle (Onopordum accanthium)

From the Wikipedia entry on this invasive weed: Onopordum acanthium (Cotton thistle, Scotch thistle), is a flowering plant in the family Asteraceae. It is native to Europe and Western Asia from the Iberian Peninsula east to Kazakhstan, and north to central Scandinavia, and widely naturalised elsewhere.[1][2][3] It is a vigorous biennial plant with coarse, spiny

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Common Teasel (Dipsacus fullonum)

Another invasive species in the Granite Creek Watershed, and mostly in Watson Woods Riparian Preserve, is common teasel. Often used in flower arrangements, this attractive pieces, has found its way into our creeks and is taking over sections of our riparian habitat. According to Wikipedia: The genus name is derived from the word for thirst

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Tamarix (Saltcedar, salt cedar, tamarisk)

Tamarix is perhaps one of our bestter know invasive species. It is found widely throughout the Southwest. The description below comes from Wikipedia, where you can read more in depth on the subject. They are evergreen or deciduous shrubs or trees growing to 1–18 m in height and forming dense thickets. The largest, Tamarix aphylla, is an evergreen tree that can grow to 18

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Russian Olive (Eleaganus angustifolia)

Acc ording to the National Park Service: Russian-olive is a small, usually thorny shrub or small tree that can grow to 30 feet in height. Its stems, buds, and leaves have a dense covering of silvery to rusty scales. Leaves are egg or lance-shaped, smooth margined, and alternate along the stem. At three years of

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What Weeds are Considered Invasive Species in This Area?

The priority species for the Upper Granite Creek Watershed are: Dalmation Toadflax (Linaria dalmatica), Diffuse Knapweed (Centaurea diffusa), Russian Knapweed (Acroptilon repens), Spotted Knapweed (Centaurea maculosa), Malta Starthistle (Centaurea melitensis), Sweet Resinbush (Euryops subcarnosus), Scotch Thistle (Onopordum accanthium), Common Teasel (Dipsacus fullonum), Saltcedar (Tamarix ramosissima), and Russian Olive (Eleaganus angustifolia) Over the next few days

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Improve the Watershed – Volunteer Opportunity

Join Prescott Creeks on an invasive species removal spree. We’ll teach you about the invasives, why they’re the bad-nasties we want out of the watershed, what they’re doing to the habitat and water quality, and what you can do about and to them. Then, we’ll take up all of their space by seeding native grasses.

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Invasive Weed Control Project

This April, Prescott Creeks is launching a project to control invasive weeds in the Granite Creek Watershed and we need your help! Not sure what an invasive weed is? Invasive weeds are plants that (1) are not native to the US and (2) are a harm to human health, or cause economic or environmental harm. 

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Volunteer Opportunity-Invasive Species Survey

–Last month I mentioned that Prescott Creeks is working on an invasive management plan for Watson Woods, being composed by Mari Echevarria for her senior project at Prescott College.  For the past few weeks, Mari and I have done a lot of work in the office and out at Watson Woods learning about 4 specific species-Scotch

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Dirt from the Field-October 2011

So far so good-I have been working here at Prescott Creeks as the Field Projects Coordinator for almost 2 months, and I am already feeling a strong connection with Prescott.  My co-workers are great, I have met lots of cool people who are passionate about the environment, and I am beginning to understand the challenges

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