Why are wildflowers endangered

It is uncertain if marked the end of the drought or is only a temporary reprieve. Tree ring records of climate in the Southwest for the last years show many droughts lasting 15 to 25 years. As the drought extended, the number of prickly poppies began to fall. By , the total had fallen to plants, a 68 percent reduction from the number in the late s.

Worse yet, the populations in four canyons had disappeared completely and had dropped to four or fewer plants in two other canyons. As concern for the prickly poppy grew, more time was spent looking for seedlings and young plants. Seedlings were seen as early as February in the lower parts of the canyons, but every drought year had the same result. With no spring moisture, the seedlings all died before the summer rains began in July and August.

How long can prickly poppy populations persist with the death of older plants, no recruitment of new plants, and depletion of the soil seed bank as seedlings die? Populations are already gone in four canyons and natural dispersal is unlikely to replenish these populations anytime soon. Continued drought could lead to extinction of the Sacramento prickly poppy.

Several recovery projects for the Sacramento prickly poppy have been tried or are being planned. In one project, members of the local chapter of the Native Plant Society of New Mexico volunteered to water prickly poppy seedlings to see if supplemental water would carry them through the dry spring.

A watered plot and a non-watered control plot were set up. The volunteers carried water in backpack sprayers and watered the plants once a week for several months.

Unfortunately, this effort was unsuccessful because seedling survival in the non-watered control plot was higher than in the watered plot, which in both cases was less than 10 percent when the watering ended. In another project, the Forest Service, University of New Mexico, Rio Grande Botanical Garden, and State of New Mexico planned to supplement one population that formerly had about plants, but by had dropped to only four plants, with plants grown at the botanical garden.

However, when the team visited the site in the early fall of , they discovered many healthy young plants that had come up with the unusually heavy and prolonged summer rains. They decided instead to monitor the young plants to see if a new cohort of prickly poppies would become established and bring the population back to former levels. If that happens, even if the drought resumes, these plants could keep the seed bank replenished for at least the next decade. The Sacramento prickly poppy is an herbaceous perennial that lives years.

Adult plants have a deep taproot and will produce some fruit even in very dry years. A healthy adult plant produces several thousand seeds per year. The seeds fall from the dried capsules and have no special adaptations for long-distance dispersal. A few seeds are dispersed by water or perhaps by ants. The length of seed viability in the soil is unknown, but attempts to germinate seeds held in controlled-climate storage for 6 years failed completely indicating that seed viability likely is less than 6 years.

Photo by Robert Sivinski. When designated as endangered, there were about 1, Sacramento prickly poppy plants in ten canyons with a total range of about 20 miles. Nearly 90 percent of the plants were in four canyons with populations of no more than 20 plants in any of the other six canyons. Rarity itself leads to an increased risk of endangerment and extinction, because rare plants with few and small populations are less able to recover from random events that wipe out individuals or entire populations.

For example, the small size of the only known population of showy stickseed, Hackelia venusta, is a major barrier to its recovery. The small number of individuals roughly plants remaining in the sole population located in Tumwater Canyon makes H. A single random environmental event could extirpate a substantial portion or all of the remaining individuals of this species, leading to extinction.

The hardest work of rare plant conservation comes with the last group, where the natural causes of rarity and the human causes of rarity have to be teased apart before it is possible to find conservation solutions. Hackelia venusta. Photo by Ben Legler. Breadcrumb Home Celebrating Wildflowers. Why Are Some Plants Rare? See Invasive Plants for more information… Disease organisms and predators are not often documented as causal agents in the decline of rare species.

In Summary Rare plants fall into several general categories of risk: Those that appear to be doing just fine, regardless of their rarity Those that are in trouble for obvious human-caused reasons Those that are in trouble for obvious natural causes Those that are declining for no obvious reason The hardest work of rare plant conservation comes with the last group, where the natural causes of rarity and the human causes of rarity have to be teased apart before it is possible to find conservation solutions.

Celebrating Wildflowers. CREW works with groups of volunteers who are capacitated to look for threatened plants in the field, with the aid of field identification sheets. Volunteers systematically survey sites with natural vegetation, and in the process identify the properties with natural vegetation in the best condition and with the highest concentration of endemic species.

Data collected by CREW volunteers is used to update information of threatened plants for Red Listing and land-use planning. In other cases, the Forest Service, with the assistance of our partners, actively manipulates habitats of rare plants to reverse or minimize identified threats. Examples of this type of management include invasive species control, reintroduction of fire into an ecosystem, or thinning the forest canopy, such as when an oak savanna is converting to an oak forest and a rare species is being shaded out.

The following present portraits of three rare, but not endangered, plants that occur on the national forests and grasslands; each represents a different life story.

Plants that occur on Appalachian shale barrens are true survivors. The extremely droughty and hot conditions keep unwanted guests out of this rare habitat. Photo by Steve Croy. Millboro leatherflower is a strict shale barren endemic, known from shale barrens that occur in Bath, August, and Rockbridge counties in western Virginia on the George Washington National Forest.

Approximately 18 occurrences are known in these habitats. The total global population is estimated at to individuals. Millboro leatherflower populations are stable and thriving at known sites. These shale barrens are self-maintaining plant communities. No adverse conditions have been identified that would modify the shale barrens community and threaten the millboro leatherflower populations.

It flowers in September to March. Fruits are 5-valved capsules. This is a species that can be easily overlooked because of its scraggly appearance! The Senecio exuberans is a perennial herb with thickened woody rootstock, up to 1. Leaves are long and narrowly oblong with long, slender petioles; upper leaf surface smooth and shiny green, lower leaf surface is duller with raised veins; thickened leaf margins wavy with rounded serrations.

Flowers are yellow, borne on the tips of the tall branched flowering stems, consists of many tiny flowers florets arranged into dense heads.

It is said to flower from December to January. It has silky hairs which remain attached to the seeds and enable the seeds to be dispersed by wind. Plantae novae africanae Senecio exuberans. The Journal of South African Botany. Apocynaceae is a family of flowering plants that includes trees, shrubs, herbs, stem succulents, and vines. It has small tubers, egg-shaped, often 2 or 3 to a plant.

The stem is single, upright, simple, or branched at the base, and with dense fine short soft hairs. Leaves are broad, egg-shaped; lower leaves are opposite, upper leaves whorled, slightly and minutely hairy along the rolled margins and on the midrib beneath, otherwise smooth, or nearly so. Flowers rotate or they are slightly reflexed, egg- shaped, almost sharp, and smooth on both sides. It flowers from December to February.