Category Archives: Nature Notes

What’s Growing on That Red Cedar?

Posted on May 28, 2013 by Stu

Perhaps the strangest things that you might see each spring are the bright orange globs hanging in the eastern red cedar trees. They look a bit like orange marmalade being pushed through a garlic press. Moist to the touch and about the size of a golf ball, these ornaments adorning the cedars are actually fungi.

The life cycle of the cedar-apple rust fungus (Gymnosporangium juniperi-virginianae) depends on both apple and eastern red cedar hosts. It’s possible to find cedar-apple rust anywhere east of the Rocky Mountains where eastern red cedars and apples coexist.

For most of the year cedar-apple rust is hard to see. However, when spring rains moisten the hard brown kidney-shaped galls that over winter on cedar trees they develop bright orange spore horns. These are very conspicuous and make the cedar look like it’s fruiting. The spores are then blown, sometimes several miles, onto apple trees infecting young buds and leaves. Over the course of the summer the fungus matures and eventually spores are blown back to the cedar trees to overwinter as small galls.

The fungus does not permanently harm the eastern red cedar trees. However, if left untreated, cedar-apple rust will damage apple fruits to the point of making them unsellable. This is a major concern for orchard owners. Today, fungicide is used to prevent cedar-apple rust from destroying crops, but that wasn’t always the case.

In 1914, apple growers wrote the Cedar Rust Act of Virginia allowing them to destroy cedar trees on neighboring property in an effort to control the fungus. While most people enjoy eating apples, a lot of people also like eastern red cedar trees, especially if they’re on your own property. You can imagine how people reacted when they woke up to see their neighbors cutting down all their cedar trees.

This all came to a head in a classic 1928 court case where a judge determined that apple trees were more valuable than cedars, and therefore more worthy of protecting. Cedar tree owners would not be compensated for their losses, but would be allowed to keep the wood from the cut trees. Remember to thank those folks who lost all their cedars next time you bite into a delicious apple!

If you happen to be out on the next rainy day, try to find an eastern red cedar. Hopefully you’ll have a new appreciation for those bright orange galls and their complex history.

Have you seen cedar-apple rust fungus before? Tell us where and when in the comments!

Attack of the Garlic Mustard

Posted on May 15, 2013 by Rosemary

The name of this plant may conjure thoughts of a tasty meal. But for gardeners and native plant lovers, garlic mustard has a bitter flavor: it’s an invasive species brought over by the settlers in the 1800s, and it’s taking over yards and forest floors.

How did garlic mustard (Alliaria petiolata) move from spicing up a few colonial gardens to dominating the northeast? Here are just a few of this plant’s clever adaptations:

  • Its roots leach chemicals that destroy the important fungal partners of nearby plants.
  • It makes a type of chemical antifreeze that helps it stay green in cold weather, allowing it to shoot up as soon as the snow is gone.
  • Each plant can release a thousand or more seeds.
  • Even after you remove the plant from your yard, its seeds can hang out in the soil for five years (or more).
  • It is toxic to some insects. Some types of butterfly eggs laid on its leaves will fail to hatch.

How to ID Garlic Mustard

Garlic mustard’s most iconic features are its green heart-shaped leaves with deep veins and tiny four-petaled white flowers. Note that the flowers don’t appear during the plant’s first year. You can also employ the smell test: true to its name, when crushed it gives off a garlicky smell.

Removing Garlic Mustard

May into early June is the best time to remove this plant from your yard. Many of the plants are flowering, making them easy to identify, but they haven’t yet had time to make seeds.

To remove a garlic mustard plant, grab it at the very base, and twist while pulling upwards. If the soil is loose, you may be able to pull up the roots, eliminating any chance that the plant could regrow. But even if you’re only able to pull up the above-ground portion, you will have at least stopped the seed-making process for this year.

Once you’ve picked the plants, put them in a plastic bag for disposal. Don’t dump them in your compost heap, or they may re-root or release seeds. Whatever you do, be sure to keep at it—because of those long-lasting seeds, you may be battling garlic mustard for years to come.