Irma visited my 40-plus-year-old citrus trees with flooding and sludge from the St. Johns River. These are trees my father planted and have always produced fruit in spite of no care. They’ve survived more than one hurricane, snow and season of drought. But never anything like this. Am I going to lose them?

 

It’s too soon to know what impact the flooding and standing water will have on your trees. And one tree may not respond like another. It depends mostly on the soil.

All plant roots, whether it’s a tree or a tulip, require oxygen for respiration and growth. In addition to oxygen in the air, oxygen in the soil exists in the spaces between particles of sand, clay and loam and water that make up the land surface. Our Florida soil typically contains around 20-21 percent oxygen. After heavy rains and flooding, the oxygen is replaced by water, and the plant can’t “breathe” and can literally drown.

Therefore, the plant’s chances of survival depend on how quickly the root ball drains. If the roots stand in water for three or more days when soil temperatures are relatively high (86-95 degrees Fahrenheit), the chance of injury is high.

It’s not just oxygen deficiency that will damage and kill roots. Types of bacteria that grow only in the absence of oxygen, and fungi such as root and foot rot quickly grow in flooded soil. These organisms can also kill a tree.

Almost all trees respond the same way when it floods. They develop water stress-like symptoms as citrus roots begin to die. Once the soil dries out, start looking. If the roots are not badly damaged, the tree can quickly begin to regenerate its fine feeder roots. While the tree is trying to repair itself, it will be especially vulnerable to insects and disease. Good growing practices will be important. The UF publication, “Citrus Culture in the Home Landscape” will be helpful to you (edis.ifas.ufl.edu/hs132).

Water stress symptoms may show up in a few days or a few weeks. Look first for wilted leaves, followed by sudden heavy leaf drop. The reason is simply that when roots are damaged, the tree cannot take up sufficient water. Sometimes the tree will drop all of its leaves and die. Often, the tree will lose only some and seem to recover. In fact, the tree, with its now shallow and damaged root system, will continue to decline and will be susceptible to drought when the dry season returns. It may be next spring when conditions are hot and dry before the true health of the tree is known.

You’ll see twig dieback and leaves with an abnormal yellow pattern (chlorosis) due to the plant’s inability to develop chlorophyll.

Inspect your trees for injury from floating debris. Prune away any broken limbs. Remove as much of the river sediment from around the tree as you can and return it to its original grade.

And then you wait. Trees planted in different locations with differently draining soil will not suffer the same fate. Only time will tell.

Since Irma, I have places in my house, garage, and even the steps to my home that are black with mold. I recognize that molds can be dangerous to our health and want it gone. Help.

The University of Florida warns that some people are more susceptible to the effects of mold than others, but that long-term or heavy exposure is unhealthy for anyone. Spores can be inhaled, absorbed through the skin or ingested on our food. Exposure can trigger allergic reactions, asthma and other respiratory issues. Infants, older people and those with compromised immune systems can be particularly susceptible. It’s clear, then, that removing mold completely and safely is an important job, and knowing where to go for knowledgeable and dependable information is critical.

As I started researching this concern that so many of us share, I began to understand how complex the process can be — far more than a mere Saturday morning column is needed to address it adequately. So, instead of treatise on mold, I want to provide you with some resources that not only provide more information but which can be customized to your particular situation.

Start online, if that’s available to you. The CDC, along with the EPA, FEMA and the National Institutes of Health have collaborated on the “Homeowner’s and Renter’s Guide to Mold Cleanup After Disasters.” It’s thorough, detailed and up to date. Needless to say, the University of Florida and other universities, plus the State of Florida, offer science-based publications.

If you’re better with a telephone than with a computer, Melanie Thomas is the Housing & Energy Conservation Agent at the Duval Extension Office. She can help you with specific housing questions as well as providing you with general information publications. You can reach her and the other agents at (904) 255-7450.

Of course, you can, and may already have begun the clean-up process yourself. If you haven’t, keep these very important steps in mind:

• All the sources I’ve found begin with wearing protective cleaning-type gloves, masks and safety goggles. Not only were the flood waters contaminated, but you may find dangerous debris left behind. Additionally, cleaning products and chemical fumes can be toxic.

• Remove anything that was wet and not dried completely in 24-48 hours. Take photos as you go for insurance purposes.

• Open all the doors and windows to begin airing out the building.

• Use a wet/dry shop vacuum to pull out as much water as possible. Close doors and windows and use fans and dehumidifiers. If possible, set your air conditioner thermostatas high as it will go for a couple of hours to allow the moisture to evaporate. Then, turn it to 70 to allow the system to begin dehumidifying.

• Clean hard surfaces with water and bleach. Remove any visible mold, and dry thoroughly.

• Don’t mix cleaning products and use them only for the purposes listed on the label. Follow all label instructions.

If you find the job is more than you can handle, look for a professional mold remediation contractor or one of our local pest control companies with special training and equipment to help you. Be aware that there are people going house to house presenting themselves as remediation specialists. Reputable companies aren’t canvassing neighborhoods. Just say no. Check their credentials with the Better Business Bureau, and their licenses with the Florida Department of Business and Professional Regulations.

And to conclude this morning’s sermon on the mold, don’t believe what you read on social media. There is a post going around that a mixture of vinegar and hydrogen peroxide will clean and kill mold spores. It won’t. Don’t bother. You have better ways to spend your time.

Paula Weatherby is a master gardener with the Duval County Extension Service and the University of Florida/IFAS. If you have gardening questions, you can speak to a master gardener from 9:30 a.m. to noon and 12:30 p.m. to 3:30 p.m. Monday through Friday at the Duval extension office at (904) 255-7450.