We may be surrounded by trees in the Pacific Northwest, but they didn’t just spring up like magic. In fact, genders are not just for humans and animals. As any Portland arborist can tell you, there are indeed male and female trees.
Granted, the terms “male” and “female” are incredibly awkward when being used in the context of trees. This is because while flowers of trees need to be fertilized with pollen to produce fruit, plant sexuality is nowhere near as rigid as it is in humans and animals.
But if that’s the case, how exactly can one tell the difference between a male and female tree?
Here are some things to consider when trying to differentiate between the two:
Trees can have either male or female parts. It is easier to see this if the tree has flowers because female flowers have ovaries that can be turned into fruit and male flowers contain pollen that can be used to fertilize those female flowers.
This can get tricky when it comes to trees because some trees have only male or female flowers, which means the tree’s gender would match the gender of the flowers. And if that was all there was to it, the identification of tree gender would be easy. However, there are many trees that contain flowers that feature both male and female genders.
In addition, there are also trees that do not contain any flowers at all, making it even harder to figure out the tree’s gender.
If a tree is dioecious it only has male or female parts, not both. If a tree is male and contains flowers, then it has male flowers and produces pollen. Meanwhile, if a tree is female and contains flowers, then it has female flowers and produces fruit. There are a lot of fairly common trees that serve as examples of dioecious trees including white ash (Fraxinus americana), ginkgo, and boxelder.
If a tree is monoecious, that means it is harder to discern a male tree from a female tree. To be clear: A monoecious tree has both male and female parts. Thus, if it contains flowers, it could have male flowers and produce pollen, as well as female flowers and produce fruit.
A common example of a monoecious tree is an Eastern white pine (Pinus strobus). A pine tree has the ability to make pine cones on its own without any help from other members of its species, though admittedly, self-fertilization is not ideal for a monoecious tree or any tree for that matter.
With this being the case, generally, monoecious trees have ways of making self-fertilization difficult. Among the ways self-fertilization becomes difficult includes physical separation, with the male flowers on top and the female flowers on the bottom, resulting in fairly easy fertilization.
Millions of people have allergies and one of the most common allergies is to pollen. Only male flowers produce pollen, so if you are allergic to pollen and begin sneezing while standing around a tree, then that tree has male flowers and is a male tree.
Sexual Features That Are Secondary in Nature
First, figure out if the tree you are looking at is dioecious or monoecious. Once you determine that, you should try to find other distinctive male and female traits so that the gender identification process can be as foolproof as possible for you.
One example would be a common persimmon tree known as Diospyros virginiana, which is dioecious. In this case, male persimmon trees contain flowers, so you can look out for those as they will appear in clusters. Conversely, a female persimmon tree would contain big, single blossoms instead.
If the tree has flowers, then keep in mind when looking for male traits that the tips of male flowers on the cedar of Lebanon, also known as Cedrus libani, are filthy looking when pollen season is in full effect. In the case of date trees, many people with advanced knowledge of trees have now been taught to recognize male and female date trees by specific genetic differences. That is a very positive development because date trees are very tough to tell apart before they fruit.
Having said that, it is important to have a professional like a Portland arborist make this determination, as an untrained person is unlikely to be able to spot the genetic differences between various kinds of trees.
Complex Sexual Reproduction
No matter what, it is crucial to always remember that not only is tree sexuality very nuanced and different from human and animal sexuality, so too is the sexual reproduction process.
While we have already established that some trees have flowers that contain both male and female parts, within the scope of those specific trees, it is important to remember that some flowers actually have sexual parts that either do not function or function only occasionally. In other words, some of the sexual parts of a flower on one of these trees are more or less for display purposes only.
In addition, like fruit that you can only buy during certain months, there are trees that are sexual seasonally. Yes, believe it or not, there are trees that can change sex from season to season. Even some trees that do not change seasonally can still change from time to time, with some trees changing once or twice during its lifetime.
The fact that there are this many wrinkles to a tree’s sexuality makes the entire process for gender identification so complex that attempting to go through it on your own can be a fool’s errand. It is without question that given all the layers and intricacies involved in figuring out if trees and the flowers on said trees are male or female, if you are not a tree expert, it is in your best interest to call a tree expert like a Portland arborist to help you figure out everything you need to know about a tree’s sexuality and how this will impact the varieties you bring into your yard.