Among the many species of pines, the 'Jerusalem pine' (Pinus halepensis), also known as the Aleppo pine, is the one most commonly found in Israel and, of course, at Ramat Hanadiv. Although not planted in the park, Aleppo pines tend to 'escape' from the groves where they were planted (around the park's borders) and colonize natural habitats nearby, a phenomenon that has been noted both in Israel and in other places around the Mediterranean basin.
The role of pines in Israel's landscapes is strongly associated with past ideology and decisions, and a handful of emotions. Pine colonization is assumed to influence the park at various aspects and levels, including ecological, functional, visual and amenity value. These and other aspects of the pine trees' influence on their surroundings have been and continue to be studied here at Ramat Hanadiv and elsewhere in Israel.
Right now, during the peak of our summer heat, the presence of Aleppo pines in the Nature Park is being observed from another perspective: how they affect the soil. This study is examining how, and to what extent, a single pine tree can impact its environment in an increasingly wide area, starting from the tree's trunk and going outward several meters from the tree's canopy. Our researchers are testing to discover exactly how much this tree and the needles it sheds affect the concentration of organic materials and especially the nutrients in the soil (primarily nitrogen and phosphorus, the most important elements for the growth of plants). They have been using special drills to collect soil samples at different distances from the trees; the samples are sent to the Hebrew University (Faculty of Agriculture) laboratories in Rehovot for analysis.
In the field, every tree and its surroundings are being carefully characterized according to certain criteria such as the tree's height, the density and diameter of its canopy, the composition of the vegetation growing beneath and around it, the thickness of the litter (pine needles) layer around it, and the amount of stones in the surrounding soil.
The research is being carried out by Rebecca Walker, an American BA student from the University of Virginia, who came all this way to study our pine trees in cooperation with Ramat Hanadiv's scientific staff. After hearing a lecture about the colonizing pine trees in the Nature Park, she became interested in the topic, first because of its ecological significance, and second, because of the Aleppo pine's historic role in the local landscape. Rebecca is fascinated, too, by the human landscape of Israel, and was delighted to have the opportunity to spend time here as a research fellow at Ramat Hanadiv and as a tourist getting to know our country.