Common Buckthorn Traditional Cache

Common Buckthorn does indeed have thorns, even though they don't show much, so be careful. Do notice the huge dying White Ash next to it.

Common Buckthorn

Rhamnus cathartica (buckthorn, common buckthorn or purging buckthorn) is a species of small tree in the flowering plant family Rhamnaceae. It is native to Europe, northwest Africa and western Asia, from the central British Isles south to Morocco, and east to Kyryzstan. It was introduced to North America as an ornamental shrub in the early 19th century or perhaps before.

Description

Rhamnus cathartica is a deciduous shrub or small tree growing up to 10 metres (33 ft) tall, with grey-brown bark and spiny branches. The leaves are elliptic to oval, 25–90 millimetres (1–4 in) long and 12–35 mm (0.5–1 in) broad; they are green, turning yellow in autumn, and are arranged somewhat variably in opposite to subopposite pairs or alternately.

The flowers are yellowish-green, with four petals; they are dioecious and insect pollinated.

The fruit is a globose black drupe, 6–10 mm (0.2–0.4 in) diameter and containing two to four seeds; it is mildly poisonous for people, but readily eaten by birds, which disperse the seeds in their droppings.

Toxicity

The seeds and leaves are considered toxic to humans and animals, causing stomach cramps and laxative effects thought to serve a function in seed dispersal. The chemical compounds responsible for this laxative effect are anthraquinone and emodin.

In 1994, R. cathartica was implicated in the outbreak of an idiopathic neurological disease in horses, although no causative agent was officially identified. In trials where rodents were fed the leaves and stems of R. cathartica, glycogen metabolism became abnormal and glycogen deposits formed in the cytoplasm of liver cells. Abnormalities in glycogen metabolism lead to diabetes in humans.

Ecology

Rhamnus cathartica is shade-tolerant, moderately fast-growing and short-lived. 

This species is the alternate host for the important rust disease of cereals caused by Puccinia coronata. Rhamnus cathartica is also the primary overwintering host in North America for an important agricultural pest of soybeans, the soybean aphid.

Allelopathy

Secondary compounds, particularly emodin, have been found in the fruit, leaves, and bark of the plant, and may protect it from insects, herbivores and pathogens. The emodin present in R. cathartica fruit may prevent early consumption, as it is found most in unripe fruits, which allows seeds to reach maturity before being dispersed. Birds and mice significantly avoid eating unripe fruits, and if forced to ingest emodin or unripe fruit, the animals regurgitate the meal or produce loose, watery stools.

Alleopathic effects of exudates from R. cathartica leaf litter, roots, bark, leaves and fruit may reduce germination of other plant species in the soil. Soils in buckthorn-dominated areas are higher in nitrogen and carbon than normal soils, which speeds up decomposition rates of leaf litter. This can result in bare patches of soil being formed and R. cathartica performs well in such disturbed habitats, so this may be adaptive for the setting of its seed.

In North America

The species is naturalized and invasive in parts of North America. Rhamnus cathartica has a competitive advantage over native trees and shrubs in North America because it leafs out before native species. 

Uses

The bark and fruit of Rhamnus catharticus were used as a purgative in the past, although their potentially dangerous violent action and side-effects means they are now rarely used. The wood is hard and dense, but little-used.

Control methods

Rhamnus catharticus is difficult to control in its invasive range, because it sprouts vigorously and repeatedly from the root collar following cutting, girdling or burning. Herbicide application to newly cut stumps is a popular and effective control method, but seeds stay viable in the soil for several years before sprouting, so repeated treatments and long-term monitoring of infested areas is required. 

The cache is a tied in, camoed "small" pill bottle, the push hard to open and close kind. It holds a rolled log with a rubber band in a tiny plastic bag. Please BYOP, no tweezers and put it back the way you found it, or better.

 Even though the road looks perfectly fine to drive, as you can see from the signs, you are not allowed to. I have seen the gate closed and locked.