Roots, Shoots, Fruits & Flowers: Brown Rot, Tree ID, Fig Planting, & Southern Blight

A fig with brown rot.

Mayhaw fruit with brown rot. Image: Kelly Self.

Brown Rot

Kelly is already harvesting fruit from her mayhaw trees and saw some infected fruit, “We just picked mayhaws at my parent’s home for the first time this year and saw several of the attached image. I looked it up and thought it might be quince rust. What do you think? They have 6 bushes/ trees planted on their property. How can I treat this? And is the fruit without it okay to use? Thanks for any advice!”Kelly is correct that quince rust is a problem in mayhaws, but there is another fungal disease affecting Kelly’s fruit, and it is brown rot (BR), a fungal disease. Amy Grant, a gardening writer for www.gardeningknowhow.com , wrote specifically about BR infecting mayhaws and shared these practices to contain BR:

  • “To manage twig infections, prune 4 to 6 inches (10-15 cm.) below the dead tissue. Then, if possible, burn the infected portions or bury them.”
  • “Sanitize pruning shears between cuts in either a diluted bleach solution or in alcohol.”
  • “To avoid infection in the future, remove and destroy any Prunus species on the property and dispose of any rotting or mummified fruit. Again, if possible, burn or deeply bury them.”
  • “Prune the tree so that it has a vase shape which will allow for greater air and sunlight penetration, as this will then allow the foliage and fruit to dry more rapidly.”
  • “Also, thin fruit so it doesn’t touch and allow transfer of the disease.”
  • “Lastly, if you have had a history of brown rot in your landscape on other fruit trees, be sure to apply either a liquid concentrate or natural copper-based fungicide in the spring prior to any symptoms appearing.”

As always, read the label for safe and effective results.

Large green fig leaf.

Leaf is probably from a Celeste fig. Image: Jeff Vincent.

Tree ID

Jeff wrote, “I reached out to LSU AgCenter to see if they could help identify this tree and they pointed me in your direction. I found this tree in Beauregard Parish on my road while walking and identifying trees with my kids. I have not seen this one before and it stands out because of the HUGE leaves. Would you be able to identify this tree? I have attached the pic I took of a single huge leaf. The tree trunk itself was only about maybe 2 in diameter so it seemed like a very young tree.” AHA checked an AgCenter publication, Figs for Commercial and Home Production, to look at images of fig varieties, and Alex’s leaf resembles the Celeste variety of fig. This variety is popular for both its fruit and its cold hardiness. The publication is available online as a downloadable document.

A fig hanging from a tree.

Celeste fig is a popular variety. Image: LSU AgCenter.

Fig Planting

Alex asked a planting question, “When is the latest time I can plant a fig? I know fall-winter is the best time. I have new figs 1 is bare root dormant and one is a potted one and sprouted. Should I just leave them potted and plant in October or will they be ok to plant now?”Alex is correct that the best time to plant woody shrub and trees is in the fall and early winter. However, figs can be rooted easily so planting at this time is feasible. Avoid sunny, windy, warm, dry days for planting. Your fig will be grateful if you plant on a cloudy, calm, cool, humid day. Irrigating with six gallons of water per square yard per week will be like one inch of rain per week.

An infected onion plant.

Green onions infected by southern blight. Image: Dr. Raj Singh, LSU AgCenter

Southern Blight

Dr. Raj Singh, the AgCenter’s “Plant Doctor,” reported that “southern blight [SB] has started to show up in Louisiana vegetable and ornamental production” because of recent warm, humid weather. SB is found in the soil and affects a wide range of vegetable and ornamental plants." Dr. Singh also adds, “The fungus attacks the lower stem of plants at or near the soil line during warm and wet conditions. Initial symptoms appear as wilting and yellowing of leaves. The lower stem becomes necrotic, and the whole plant eventually turns brown and dies.”Dr. Singh recommends, “Management of southern blight starts with avoiding planting susceptible crops in areas known to be infested with the pathogen for two or more years.”

He adds, “For small plantings, aluminum foil may be wrapped around the lower part of the stem from just below the soil line to approximately 2 inches above the soil. This provides a physical barrier that prevents the pathogen from reaching the plant. Remove infected plants and discard them properly. Do not compost the disease plants. Movement of infested soils should be minimized to prevent pathogen spread. Cleaning farm equipment to remove dirt is recommended.”

If you want to contact Roots, Shoots, Fruits, and Flowers, please send your questions and pictures to Keith Hawkins, Area Horticulture Agent (AHA), 337.284.5188 or khawkins@agcenter.lsu.edu .

“Before you buy or use an insecticide product, first read the label, and strictly follow label recommendations. Mention of trade names or commercial products in this article is for informational purposes only and does not constitute endorsement by Louisiana State University AgCenter.”

“This work has been supported, in part, by the USDA National Institute of Food and Agriculture, Renewable Resources Extension Act Award, Accession Number 1011417.”

5/8/2024 6:51:29 PM
Rate This Article:

Have a question or comment about the information on this page?

Innovate . Educate . Improve Lives

The LSU AgCenter and the LSU College of Agriculture

Top