Sunday, June 24, 2007


Lopping, also known as tree lopping and topping, is the practice of cutting trunks and branches of a tree in an effort to contain the tree's size or shape. Lopping is differentiated from other styles of pruning by where the cuts are made. When a tree is lopped, the cuts are made internodally, or not at branch unions and collars at the correct angles, leaving a piece of protruding timber that is called a stub.

Lopping in many cases is careful an inappropriate pruning method for amenity trees. The lopped stubs may regrow adventitious epicormic shoots which are bonded only to the bark. These epicormic shoots can grow dynamically and, unless regularly pruned off, may outgrow the original height and spread of the tree. Further, the ends of the lopped stubs are exposed to pathogens which may enter and infect the tree.

Sunday, June 17, 2007

Neem Oil

Neem oil is a vegetable oil pressed from the fruits and seeds of Neem, an evergreen tree which is endemic to the Indian sub-continent and has been introduced to many other areas in the tropics. It is perhaps the most significant of the commercially available products of neem.Neem oil is typically light to dark brown, bitter and has a rather strong odour that is said to join the odours of peanut and garlic. It comprises mainly triglycerides and large amounts of triterpenoid compounds, which are in charge for the bitter taste. It is hydrophobic in nature and in order to emulisify it in water for application purposes, it must be formulated with suitable surfactants.

Sunday, June 10, 2007

Water Abstraction

Water abstraction, or water extraction, is the process of taking water from any source, either temporarily or permanently. Most water is used for irrigation or treatment to produce drinking water.Depending on the environmental legislation in the relevant country, controls may be located on abstraction to limit the amount of water that can be removed. Over abstraction can lead to rivers drying up or the level of groundwater aquifers reducing unacceptably.The science of hydrogeology is used to assess safe abstraction levels.