Identifying Weeds

Most of us can spot a weed in our garden. But, sometimes a new plant will pop up that you’re fairly certain you didn’t put there. Is it a weed? Or, is it an ornamental that was dropped in your garden courtesy of Mother Nature.

Last spring I had a bunch of "weeds" pop up. I started to pull them out but stopped when I realized that they were a little more attractive than the average weed. My neighbor (who has a beautiful garden) just happened to be passing by. She told me they were Snapdragons. Then it hit me. I planted a Snapdragon last year, which in my area is an annual. I pulled it out at the end of the season. But apparently it had set seed.

So, next time you’re weeding and come across a plant that you’re not sure about, look it up on one of the following sites that help with weed identification.

Iowa State Weed Science
National Gardening Association Weed Library
The Organic Weed Management Website
Virginia Tech Weed Identification Guide
University of California Weed Photo Gallery

Identifying Poisonous Plants

It goes without saying that it’s a good idea to know if your plants are poisonous to humans or animals. Unfortunately, it’s difficult to find one database or resource that gives a complete list of all the poisonous plants in the United States. Here are few sites that you can visit if you’re trying to determine if your plants are toxic:

Cornell University’s Plants Poisonous to Livestock Database
US Army Guide to Poisonous and Toxic Plants
Texas A&M University’s Poisonous Plants Publication

With the Christmas season approaching, it’s a good time to remind ourselves that some of the plants we use to decorate our homes can be harmful to pets. Mistletoe and Holly are two that can be moderately to severely toxic. I always thought that Poinsettia was poisonous, but according the Cornell site it’s not very toxic at all. Still, it’s a good idea to keep it out of the reach of pets and children.

U.S. Department of Agriculture Plants Database

A great source of plant information is the Plants Database available on-line through the United States Department of Agriculture website. This is definitely the place to go if you want to know everything from plant classification (i.e. Kingdom, Subkingdom, Division etc.) to foliage color.

When you go to the site you’ll find a Search area located at the top left side of the page. Type a plant name in the Name Search field and select a search type (Common Name, Scientific Name, Symbol). The Symbol is a unique name created by the USDA for use within the database.  The naming convention is a little complicated so if you want to search by Symbol, first take a look at the Plants Tutorial. If you’re not entirely sure how to spell a plant name or if your search isn’t turning up any results try using the wildcard character (*) in your search (e.g. chrysanth* will return all database records for chrysanthemum). You can also do a state search which helps narrow down the results.

It takes a little practice to learn how to navigate this site, but once you get the hang of it you’ll find a lot of useful information. Here’s an example to help get you started:

1. Type “liriope muscari” in the Name Search field.
2. Select the search type Scientific Name.
3. Press the Go button

A list of plant names will display. You can sort the columns alphabetically by clicking on the column titles (Symbol, Scientific Name, Common Name). This comes in handy when your search returns a long list of plants.

Now click on the entry for “Liriope muscari”. This is where you’ll see specific detail for the plant. On the right side of the screen you’ll see a link for Characteristics. Click on it to drill down even deeper into the database details. Use the information here to fill out your GardenScribe Plant Detail pages.

While you’re on this site, explore some of the interesting sections on the sidebar like “Invasive and Noxious Weeds” and “Threatened & Endangered”.

You won’t find every plant from your garden in the Plants Database. As a matter of fact it’s not really intended for common garden plants. It has mostly native and naturalized plants. But, since many of us have started to garden using native plants, I thought this would be a useful research source. Plus, they have a great list of internet links to help direct you to other plant information sources.