Garden Clippings for November 9, 2019
Evergreens are not forever green which is why horticulturists prefer to call them conifers.
The term evergreen is misleading because conifers eventually lose their needles. White Pines, for example, lose many of their needles when they area as little as three years old. They will drop their needles on the soil beneath, leaving a blanket of yellow needles that act as mulch to protect roots for the coming winter.
All conifers drop their needles. Spruce, Balsam and Fir defoliate just as readily as Pine but are less noticeable because needles are brown and shorter than those of White Pine.
The good news is that conifers grow new needles just as quickly as dropping their old, spent needles. Most old needles drop in the fall followed by new needles appearing in spring. The old needles drop from the inside of the conifer while new needles grow on the new terminal shoots.
Those who have bought fresh-cut Scotch Pine Christmas trees know that there is often a buildup of old needles in the centre of the tree. Christmas trees are sheered to maintain dense growth, but the resulting dense growth prevents old needles from falling to the forest floor. Some of these old needles lodged in the centre of a Pine can be 4 or 5 years old.
In home landscapes, conifers play a key role. Their evergreen foliage offers year-round greenery for privacy and wind protection. Birds find shelter through winter and look to the cones as valuable food source. The term foundation planting refers to a variety of evergreens planted at the house foundation providing insulation through winter.
In the lumber industry conifers play a huge role. Almost all lumber used for framing houses is sourced from Spruce trees who have a habit of growing both straight and quickly.
In the forest there is often little diversity in conifers. There can be hundreds of different deciduous plants in a forest with only two or three conifers in the mix. In Canada, the further north you go, the more conifers you will see. In the heavily forested West Coast ski areas, it is rare to find deciduous trees. In contrast the bush in South-Western Ontario is dominated by deciduous trees such as Maples and Oaks with only a few conifers.
The world’s tallest trees are Giant Sequoias, topping out at just over 300 feet, are found in California. The world’s oldest trees, Bristlecone Pine, are believed to be more than 5,000 years old and can be found in the desert mountains of California and Nevada. Giant Sequoias are rapid growers, while the shrubby looking Bristlecone Pines are extremely slow growing.
In South-Western Ontario, the tallest conifers are just over 100 feet, usually reaching higher than local deciduous trees, but paling in size to the trees along Canada’s West Coast.