The roots of a tree make gaps in the soil so that when it rains the water has space to move around in the soil before being absorbed. When trees are removed and the heavy machinery used in logging compacts the soil and fills all the spaces that allow air and water to get to the roots of plants, it becomes difficult for plants to continue growing or for new plants to grow.
(Compacting soil is similar to when the first snow falls. At first the snow is light and fluffy but once you start walking on it, it becomes hard and close to the ground. It is much more difficult to shovel snow when it is compacted!) When the soil is compacted, and the trees are removed, soil is not held in place by the roots and water is not absorbed by the soil and so during heavy rainfalls, it runs over the compacted soil causing floods.
Eventually, heavy rains lead to soil erosion, as the running water strips the top layer of soil away. The top layer of soil is the most nutritious and without it, it is hard for plants to grow. So, take part in Arbor Day this May by planting a tree. The Arbor Day Foundation has inspired people to plant, nurture and celebrate trees for since 1972 and was established to celebrate the 100th anniversary of the first Arbor Day.