Ecology of endangered Hand.-Mazz. in Jabal Al-Lauz, Saudi Arabia: Plant associations, size structure, and nutritional screening.

The wild has a restricted distribution in small scattered areas of Jabal Al-Lauz (2580 m above sea level), a mountain in northwestern Saudi Arabia. Major objective of current study is to provide information about by analyzing its ecology in terms of floristic diversity, plant associations, environmental features, and its size structure and nutritional value. For this purpose, 12 stands of 20 m were selected along the Jabal Al-Lauz mountain ridge. Three plant associations and their environmental variables were identified and characterized after application of a two-way indicator species analysis (TWINSPAN), detrended correspondence analysis (DCA). And canonical correspondence analysis (CCA) as follows: VGI: -, VGII: , and VGIII: -. The edaphic factor affecting the distribution of the associations were pH, potassium and manganese content. The size class frequency distribution of shows a J-shape in spring and fall for the whole population; there was no regeneration via seed. Nutritional evaluation showed the fruits had a higher content of total carbohydrate, fats, crude protein, phosphorus, and potassium, and lower content of ash, Fe, Ca, Mn, Mg, and Zn than that in stems and leaves. This ecological knowledge gained through this study would be beneficial for managing and conserving of in a Jabal Al-Lauz area with its distinct and unique vegetation.