Crabgrass & Quince Rust

Karen Cambre, Sharpe, Kenneth W.

News article for February 12, 2018

It does not take many warm days for plants to start breaking dormancy. This past weekend I saw a number of tulip magnolias and ornamental pear trees blooming away.

While the likelihood of us having more cold weather is pretty good, it is not uncommon for some of our plants to react to early warm weather. This early green up can cause more cold damage, as even light frosts will damage tender spring growth and flowers.


Crabgrass is one of those plants that will react to early warm temperatures. It is an annual grass that will germinate when soil temperatures reach 55˚F and above. Crabgrass is a common grassy weed which is present in most southern lawns. It is a heavy seed producer, with a single plant capable of producing 10,000 seeds. When you get any kind of damage or bare spot in the lawn, stored up seeds will cease the moment and germinate.

Your best crabgrass control method is to prevent seed germination. In our area it is not uncommon for crabgrass to germinate in mid-February. I use Valentine’s Day as my reminder to put our crabgrass preventers.

There are several herbicide choices but I like the ones with the active ingredient dithiopyr. Dithiopyrwill prevent crabgrass seed from emerging but if your timing is a little late, it will also kill small crabgrass seedlings. This active ingredient can be found in a number of retail products such as High Yield Dimension, Greenlight Crabgrass Preventer 2 and Sta-Green Crab-Ex.

If goose grass is also a problem in your lawn, you could use Scott’s Halt which will prevent both crabgrass and goose grass. Your application will need to be prior to seed germination as Halt will not kill crabgrass seedlings.


quince rustjpg

Over the past several years I have seen a lot of quince rust on mayhaw fruit. This is a disease that will cover the prized fruit in pimple-like bumps of orange powder, with fungal spines emerging from the fruit. This is not the mental picture I want for jelly to go on my biscuit.

Quince rust emerges from its host plant, eastern red cedar. In cedars, the disease shows up as an orange jelly like material hanging from the cedar’s limbs in April and May. Fungal spores are spread by wind and the source of inoculation could be several miles from your mayhaw trees.

The orange power and spines on mayhaw fruit will not show up until April and May, but when you see it then, it is already too late to treat. Your window of opportunity for treating mayhaws would be while they are blooming. You can spray the blooms with Immunox Multi-Purpose Fungicide when flowers first begin to open.

For any future planting of mayhaws, select varieties that have resistance to quince rust.

If you have a favorite pecan tree that you wish was yours, now would be a good time to collect grafting wood. We use mid-February as the time for collecting scion wood, but try to collect before buds start to swell. Cut two year old wood, which will be about one half inch in diameter. Select wood that is straight and has buds evenly spaced about 2 to 3 inches apart and make sure you get 2 to 3 well developed buds.

Dip the ends of your cut grafting wood in grafting wax and place the wood in plastic bags with a moist paper towel and then into your refrigerator crisper.

Whip grafts are most successful from mid- February to early March.

For more information on these or related topics contact Kenny at 225-686-3020 or visit our website at for more information.

5/9/2018 4:09:30 PM
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