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Keyword: reproductive biology

Seed and ring width data from 'Climate drivers of seed production in Picea engelmannii and response to warming temperatures in the southern Rocky Mountains'

Datasets Posted on: June 08, 2016
Seed production by Picea engelmannii was monitored at 13 plots distributed across an approximately 670 meter elevation gradient in the Fraser Experimental Forest near Fraser, Colorado. Seeds were collected annually between 1970 and 2010 from ten wire mesh seed traps located in each of the 13 plots. Annual plot level estimates of seed abundance were derived from an average value of the 10 traps.

Implications of managing the timing and intensity of herbivory for conservation of Arizona leatherflower

Publications Posted on: October 02, 2012
For rare plants, the question of whether and to what extent wild and domestic herbivores influence growth, reproduction, and survival can be critical to preservation. The sensitive species, Clematis hirsutissima var. arizonica, grows on Forest Service lands where cattle, elk, mule deer, and numerous small mammals forage. In a 3-year clipping experiment, I examined the impact of season and intensity of herbivory on reproduction and growth.

Distribution and taxonomic discussion of Tetraneuris verdiensis, an apparently rare edaphic endemic from the Verde Valley of Arizona

Publications Posted on: October 02, 2012
Tetraneuris verdiensis was first published in 1996. It appears to be closely related to Tetraneuris acaulis var. arizonica. The closest known location of T. acaulis var. arizonica is approximately 7 miles northwest of the known T. verdiensis locations, which are 5 miles east of Camp Verde. Tetraneuris verdiensis is significant in that no other entirely discoid populations, or series of populations, of Tetraneuris have been reported.

Cultural influence as a factor in determining the distribution of a rare sage, Salvia dorrii subspecies mearnsii

Publications Posted on: October 02, 2012
Although related taxa occur throughout the western United States, Salvia dorrii ssp. mearnsii is endemic to central Arizona. In part, its narrow distribution may be attributed to prehistoric human influences. A spatial analysis was used to determine the relationship of archaeological sites and populations of S. dorrii ssp. mearnsii.

Distribution of Paradine plains cactus in pinyon-juniper woodland on the North Kaibab Ranger District, Kaibab National Forest

Publications Posted on: October 02, 2012
Surveys for Paradine plains cactus (Pediocactus paradinei B. W. Benson) conducted for the Kaibab National Forest, North Kaibab Ranger District in 1992-94 qualitatively showed a fairly substantial population of scattered individuals in the pinyon-juniper woodland, and indicated that there might be a correlation between plant distribution and dripline of trees. This project was initiated in 1999 to test that possibility.

The threat of increasing hybridization of an endangered plant species, Purshia subintegra, in the Verde Valley, Arizona

Publications Posted on: October 02, 2012
The existence of the endangered shrub Purshia subintegra may be threatened by hybridization with the more common P. stansburiana. In the Verde Valley, the range of the rare P. subintegra overlaps with the range of P. stansburiana, allowing introgression to occur. Although P. subintegra and P.

Extinction risk of Ipomopsis sancti-spiritus in Holy Ghost Canyon with and without management intervention

Publications Posted on: October 02, 2012
Small populations are threatened with deterministic and stochastic events that can drive the number of individuals below a critical threshold for survival. Long-term studies allow us to increase our understanding of processes required for their conservation. In the past 7 years, the population of the federally endangered Holy Ghost ipomopsis (Ipomopsis sancti-spiritus) in Holy Ghost Canyon has fluctuated widely from 2047 to 372 plants.

Dalmatian toadflax, an invasive exotic noxious weed, threatens Flagstaff pennyroyal community following prescribed fire

Publications Posted on: October 02, 2012
Many noxious weed infestations are initiated or increased by soil disturbance. With the recent emphasis on reintroduction of fire into natural ecosystems there has been increased interest in the effects of noxious weeds following fires. This paper discusses the effects of fire on Flagstaff pennyroyal, a Forest Service Region 3 sensitive plant, and the subsequent infestation of the project area by Dalmatian toadflax (Linaria genistfolia ssp.

Preliminary report on the reproductive biology of the threatened Chisos Mountain hedgehog cactus

Publications Posted on: October 02, 2012
The Chisos Mountain hedgehog cactus (Echinocereus chisoensis, Cactaceae) is a narrow endemic restricted to an approximately 100 square mile area in Big Bend National Park, Texas. It was listed as threatened in 1987 as Echinocereus chisoensis var. chisoensis.

Quantitative genetics in natural populations: Means of monitoring natural biological processes

Publications Posted on: October 02, 2012
One of the goals of conservation biology is to maintain the integrity of natural processes in populations of rare plants. In the short term one of the main concerns is often whether the mating system of rare plants is disrupted, for example, by fragmentation.