Some of the conifers which were introduced to New Zealand have become invasive and they include radiata pine, lodgepole pine, European larch, and Douglas dir. In South Africa species such as patula pine, maritime pine, and radiata pine have been named as invasive species. Coniferous trees have several characteristics chief among these being their leaves which are why they are referred to as evergreens since they retain their foliage all year round by shedding and growing new ones simultaneously.
Leaves of some coniferous plants are needle-shaped like the pine, spruce, and fir while others such as cypress have scale-like leaves, these do not form single leaves but entire branches of more than one year.
Conifers bear cones that are seeds and they are dispersed both by wind and animals. The seed cones have bracts, which bear semblance to actual seeds. They are partly hidden in some species like hemlock, or barely visible in firs while they are seen to be elongated and very prominent in the Douglas fir. These trees typically grow wild in U.
Department of Agriculture plant hardiness zones 2 through 6. The pond cypress Taxodium ascends thrives in USDA zones 6 through 9 and is also a deciduous coniferous tree. These trees prefer full sun and adapt to a variety of soils. Some evergreen trees are neither coniferous or deciduous. Likewise, not all evergreens are conifers.
Numerous broadleaf evergreens are not conifers because they reproduce via flowers, not cones; examples include:. Beginners often become confused by these terms and end up asking the wrong questions. For example, you will sometimes hear someone wondering whether such and such a tree is deciduous or a conifer, as if it had to be one or the other.
But this is the wrong contrast to draw. The difference the person truly has in mind is between "deciduous" and "evergreen," where the issue is whether or not a plant's leaves fall from its branches every autumn. Some trees and shrubs that you may not think of as being conifers actually are. Not all cones have the appearance of a classic cone, such as the spruce cone.
Examples include:. The wisdom or lack thereof of selecting this type of plant for your yard depends on factors such as:. Conifers with large cones, such as eastern white pine trees Pinus strobus , can be some of the messiest trees to grow , creating more landscape maintenance than some people care to engage in. Furthermore, it is a double whammy if you plant such a tree in a spot near where you park your car. Not only will you be raking cones off your driveway , but you will also be cleaning pine pitch off your windshield plus those needles have a way of getting under your vehicle's front hood and taking up residence there.
These trees become bare in winter with no needle-foliage on the branches and stems. Conifers differ from deciduous broadleaved trees because of their needle-like foliage. Some types of conifer leaves on trees such as pine, fir, spruce, and larch have thin leaves that look like needles. Other coniferous plants such as juniper, cypress, and cedar, have soft scale-like leaves. When these conifers shed foliage, it is short branches that drop, not individual leaves.
The easiest way to identify different conifer species is to examine their needles. Pines have needles that grow in bundles of two to five needles on a stem. In contrast, spruce trees and fir trees have single needles that grow individually. Identifying the difference between spruce and fir trees is simple. In essence, spruce trees have stiff and sharp needles and fir trees have flexible and soft ones.
As you read about the individual coniferous types of trees, you will find out more about how to identify conifers. Later in the article, you will find out a lot more information about the most common types of conifers.
Cedars Cedrus are a group of evergreen coniferous trees that have dense clusters of needles. Cedars also produce barrel-shaped cones that point upward. False cedars are conifer trees in the Thuja , Calocedrus , and Juniperus genera.
There are over species of pine trees Pinus , and they have needles that grow in clusters of between two and five. Some species of pines have needles in bundles of seven. Pine cones usually grow in the classic conical shape.
Fir trees Abies are related to pine trees and have thin, needle-like leaves. The fir cones are cylindrical and long and stand erect on branches like candles. There are around 35 species of spruce trees Picea , and they have sharp needle-leaves.
Visually, spruces look similar to firs. However, their needles are stiffer, and their cones droop. Larch conifers Larix are a type of deciduous conifer tree whose needle-leaf foliage turns yellow in the fall before dropping off. Larch cones are small and oval or egg-shaped. Cypress trees Cupressaceae generally grow in warmer climates and have sharp, scale-like needles leaves. Cypress cones are woody and leathery and resemble large, plump acorns.
Hemlock conifers Tsuga are evergreen conifers that have foliage like short needles growing from small pegs. Hemlock cones are cylinders that range in their length. Juniper conifers Juniperus belong to the family Cupressaceae and are known for their intense aroma. Depending on the species, they have needle-like foliage or scale-like foliage. Their cones are like fleshy woody oval fruits. Yews Taxaceae have dark green foliage and pointed soft needle-like leaves.
The unique feature of yew trees is that their cones on the female trees look like round red berries. Redwoods and sequoias Sequoioideae are some of the tallest trees in the world.
Their foliage looks like tiny swords, and they are also sharp.
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