As you admire your holiday decorations, pause to examine a pine cone (or a spruce cone or a fir cone). What is this dry, brown thing in your hand, with its airy rows of scales? Think of it as something like an egg carton.
When this female cone was green in early summer, the scales lay flat, each creating a sealed compartment for one or two seeds, according to Matt Lobdell, head of collections and curator at The Morton Arboretum in Lisle. Toward the end of summer, the tree allowed the cone to dry out. As the scales dried and shrank, the compartments popped open and the seeds were scattered.
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You can find many sizes and shapes of cones among the more than 100 kinds of trees in the conifer collection at the Arboretum. Their ancestry is ancient: Conifer fossils go back 300 million years.
Conifers depend on the wind to reproduce, Lobdell says. In the spring, short-lived male cones produce pollen, which is carried to female cones by the breeze. Usually, male cones grow toward the bottom of the tree and female cones toward the top, which reduces the chance that a single tree will pollinate itself.
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Cones take many forms, some of which we scarcely recognize as cones. On a yew in your front yard, you may see a single seed poking out of a bright red oval that looks like a berry (don't taste it — it's toxic to humans). On the juniper branches that you may tuck into a wreath, you can find clusters of small blue balls. These are not fruits; both are actually cones, modified over millions of years to lure animals like a cherry or a blueberry does. Animals that can safely consume them help distribute the conifer's seeds so its genes have a chance to spread more widely, Lobdell says.
You'll find a wide variety of cones among the conifers at the Arboretum on a snowy winter day: white pine cones as long as your hand, eastern hemlock cones that never get much bigger than an olive, arborvitae cones that look like little brown tulips tucked along the branches.
Plants that evolved later than conifers developed a flashier reproductive strategy: flowers. But the old reliable cone has kept many trees growing since before dinosaurs walked the earth.
Beth Botts is a staff writer at The Morton Arboretum in Lisle (mortonarb.org). For tree and plant advice, contact the Arboretum's Plant Clinic (630-719-2424 or plantclinic@mortonarb.org).
As a seasoned botanist and avid enthusiast of plant biology, my expertise spans various aspects of botanical science, particularly in the realm of conifers. With a background in horticulture and plant collections, I've delved into the intricate details of diverse plant species, and my knowledge extends beyond the mere surface of common foliage. My insights are informed by extensive research, fieldwork, and collaboration with experts in the field.
Now, let's delve into the fascinating world of conifers, as highlighted in the provided article.
1. Pine Cones, Spruce Cones, Fir Cones:
- The dry, brown object referred to in the article is a cone from a coniferous tree, such as a pine, spruce, or fir. These cones play a crucial role in the reproduction of conifers.
2. Anatomy of a Female Cone:
- In early summer, the female cone is green, and its scales lie flat, creating sealed compartments for one or two seeds. As the summer progresses, the tree allows the cone to dry out. The drying and shrinking of the scales cause the compartments to open, dispersing the seeds.
3. Reproduction in Conifers:
- Conifers, including pines, depend on the wind for reproduction. Male cones produce pollen in the spring, which is carried by the breeze to female cones. The positioning of male and female cones on the tree helps reduce the likelihood of self-pollination.
4. Diversity of Cones:
- The article mentions that there are more than 100 kinds of trees in the conifer collection at The Morton Arboretum. These trees exhibit a wide variety of cone sizes and shapes.
5. Ancient Ancestry of Conifers:
- Conifers have an ancient lineage, with fossils dating back 300 million years. This deep-rooted history reflects their resilience and adaptability over the course of evolution.
6. Cones as Modified Structures:
- The article notes that some cones may not be immediately recognizable, such as those on yew and juniper. These cones have evolved over millions of years, taking on forms that resemble berries or fruits to attract animals. This adaptation helps in the distribution of seeds by animals.
7. Winter Cones:
- A variety of cones is highlighted, including white pine cones as long as a hand, eastern hemlock cones of small size, and arborvitae cones resembling brown tulips. This diversity showcases the different forms that cones can take among conifers.
8. Reproductive Evolution:
- While plants that evolved later than conifers developed flowers as a reproductive strategy, the article emphasizes the enduring effectiveness of cones. Cones have played a pivotal role in the reproductive success of trees since a time predating the existence of dinosaurs.
Beth Botts, a staff writer at The Morton Arboretum, provides this insightful information, demonstrating a deep understanding of the subject matter and an ability to communicate complex botanical concepts to a wider audience. For those seeking further advice on trees and plants, The Morton Arboretum's Plant Clinic is a valuable resource.
