Hawthorn, a small thorny tree preferring temperate climates, has long been cultivated as a hedge and for its ornamental white flowers. Thornless horticultural varieties are also available. The fruits are small and mealy but edible, traditionally used to make jelly and to flavor a type of liqueur, and the fine-grained wood was used as firewood and to make small items. Botanically, hawthorn is a complicated genus; there are many species that are quite variable and also hybridize freely, so that few if any "pure" populations of a species may exist. The resulting diversity has complicated the plants? nomenclature, so that many insignificant variants were described as species, and an individual plant may be very hard to identify. The name Crataegus oxyacantha L., often used to refer to C. laevigata, was discovered to have been misapplied for many years and has therefore been rejected by taxonomists.

Preparations of the leaves with flowers, and occasionally the fruits, are used medicinally for a variety of cardiovascular problems, including early-stage heart failure, functional heart complaints, high blood pressure, and certain arrhythmias. A number of placebo-controlled clinical trials have shown that leaf with flower extracts, taken over a long period of time, improve exercise tolerance and reduce angina and other symptoms in people with congestive heart failure. Hawthorn has also been found to be quite safe, with few side-effects. As a result, it is frequently prescribed by physicians in Germany, where the majority of clinical research has been conducted. Several other species are occasionally used in a similar fashion.

Selected References

Christensen, K. I. 1992. Revision of Crataegus Sect. Crataegus and Nothosect. Crataeguineae (Rosaceae - Maloideae) in the Old World. Systematic Botany Monographs vol. 35.

Phipps, J. B. 1998. Introduction to the red-fruited hawthorns (Crataegus, Rosaceae) of western North America. Canadian Journal of Botany 76:1863-1899.

Rigelsky, J. M., and B. V. Sweet. 2002. Hawthorn: pharmacology and therapeutic uses. American Journal of Health-System Pharmacy 59:417-422.

Tauchert, M., M. Ploch, and W. D. Hubner. 1994. Effectiveness of hawthorn extract LI 132 compared with the ACE inhibitor Captopril: Multicenter double-blind study with 132 patients NYHA stage II. Münchener Medizinische Wochenschrift 136 (Suppl.):S27-S33.

Weikl, A., K. D. Assmus, A. Neukum-Schmidt, J. Schmitz, G. Zapfe, H. S. Noh, and J. Siegrist. 1996. Crataegus-Spezialextrakt WS 1442. Objectiver Wirksamkeitsnachweis bei Patienten mit Herzinsuffizienz (NYHA II). Fortschritte der Medizin 114(24):291-296.

Zapfe, G. 2001. Clinical efficacy of crataegus extract WS 1442 in congestive heart failure NYHA class II. Phytomedicine 8:262-266.