Q: I saw an article in my local newspaper about eliminating cattails that are growing in a pond. In my case, they are not in a pond. They are in a bit of a marshy area that I have on my property. In the 22 years I have owned the property, the cattails have taken over more and more ground.
How do I get rid of them?
A: It is common for cattails to spread into wet soil areas around a pond. There are several things you can do. You will probably have to do several in succession to be successful.
The key to cattail control is the root system. It is the only part that survives the winter and it needs to stay moist all summer. Draining an area so the roots can freeze in the air over the winter or dry out in the summer will kill roots.
Repeatedly cutting them down or mowing them will reduce the amount of food stored in the roots, preventing them from spreading by seeds. This method will take a couple of years; however, if done several times a year it will work. Cut them off as low as possible each time. Burning the area doesn't control cattail roots, but it does get rid of the tops. It makes it easier to follow through with the other top removal methods.
Hand pulling is an organic method of cattail removal. It is best accomplished when plants are small and the soil is moist. It is messy and difficult, but it does work. Watch the area for several weeks and pull any new sprouts as soon as possible.
Machine pulling is possible with a backhoe. It is a form of dredging that is attempting to only go as deep as the roots; it doesn't try to pull out a lot of the soil. This is expensive, and can be a big problem if moist of soil is pulled out too. In a pond, it can be used to create an are deeper than cattails can grow in. It might be best to use this method in the winter when the ground is frozen and the machinery won't damage the surrounding soil with its wheels.
If you can flood the area, water can be a useful tool. Keep the area as dry as possible during the summer and cut down as many cattails as possible. Then during the winter, either leave it dry to freeze the roots or flood it to drown them. They need to breathe through the stems, so make sure they are cut off below water level.
If you want to use herbicide, you will need one labeled for cattails and aquatic use. Follow label directions for best results.
Q: We are in the middle of planting roses and have discovered a new organic mulch made of coconut husk; it is called coir. Have you ever used this product?
My wife believes it retains moisture so well that we are watering about 40 percent less than usual - our city east of San Francisco is arid and hot in the summer. We had water restrictions in place in the 1970s and could face such conditions this summer. The mulch comes in a compressed form that expands to 2 cubic feet with 5 gallons of water. It's incredible to watch the hydration.
Are you aware of this mulch? Are the benefits really as good as advertised? Our nursery swears by it, and they sell a wide variety of ground coverings. Thanks for any news or experience you have had with it.
A: You have provided a good testimony for the benefits of coir. Coir fibers are the mass of stuff that surrounds the shell of a coconut. White coir is harvested from coconuts that are not ripe. The fibers are smooth, fine and weaker than the thick brown coir fibers that come from ripe coconuts. White fibers are used to make yarn for mats or rope. Brown fibers create stronger mats and sacks. The fibers are waterproof and resistant to salt water damage.
Coir fibers and the left-over smaller particles produced in the process make an excellent organic matter that can be used to amend soil. It opens up heavy clay soils so air and water both flow better. It can also be used in sandy soils to hold moisture. It is less damaging ecologically than peat mining. For people concerned about loss of peat bogs, it would make a good organic matter substitute. Coir can be used on top of the soil as mulch. It is slowly broken down by bacteria and fungi, so it doesn't have to be added over and over again.
Do not confuse coconut coir with cocoa shell mulch. This mulch is produced during the process of roasting cocoa beans. It smells like chocolate for a few weeks, but the smell does go away. It is a pretty dark brown color, and can be a good organic mulch.
But to me, it looks like a bunch of squirrels left all their nut shells in the flower bed. It has the potential to cause trouble for dogs that eat it. Depending on how the shells were processed, the cocoa shell mulch may have high levels of toxic theobromine.
E-mail questions to Jeff Rugg at firstname.lastname@example.org.