Scale insects on a cabbage palm (Sabal palmetto). Photo Credit: Matt Lollar, University of Florida/IFAS Extension – Santa Rosa County
This week I was on a couple site visits to look on some cabbage palms (Sabal palmetto) and some banana shrubs (Michelia figo). The palms had a white, waxy substance on their frond petioles and the banana shrubs had white specs on the tops of their leaves. Upon further investigation, I realized the waxy substance and specs were both different species of scales. Scale insects are serious pests of a number of ornamental plants. Here in Florida there are 13 different families of scales with the most common being armored scales, soft scales, and mealybugs. Scales have piercing-sucking mouthparts which they use to siphon fluids from the leaves, stems, and sometimes roots of many ornamental plants. Heavy infestations cause extensive leaf yellowing, premature leaf drop, branch dieback, and eventually plant death.
Scale Biology
The life cycle of a scale begins with eggs being laid beneath wax coverings or beneath the adult female. Eggs typically hatch in 1 to 3 weeks. The newly hatched nymphs, called crawlers, move around a plant until they find a spot to feed. Once a feeding site is located, their piercing sucking mouthparts are inserted into the plant and the crawlers begin to feed and grow. The males of many scale species develop wings as adults and fly to other plants to reproduce.
Magnolia white scales on a banana shrub (Michelia figo). Photo Credit: Matt Lollar, University of Florida/IFAS Extension – Santa Rosa County
Armored Scales
Armored scales get their armor by secreting a waxy covering over their bodies that is not attached. The scale lives under this covering and uses it as a protection to feed under. Armored scales can be almost any color or shape and range anywhere from 1/16 to 1/8 inch in diameter. For females, these shapes range from circular to oval to long and slender. The males typically have coverings that are more elongate and smaller than the females. As adults, the males are tiny, winged, gnat-like insects and are rarely seen.
Gloomy scale (Melanaspis tenebricosa) with armored covering removed. Photo Credit: A. G. Dale, University of Florida/IFAS
Soft Scales
Similar to armored scales, soft scales secrete a waxy covering, but it is attached to their bodies. Soft scales can be a number of colors, shapes, and sizes and range anywhere from 1/8 to 1/2 inch in diameter. Their shapes vary from spherical to nearly flat.
Population of adult and immature tuttle mealybugs (Brevennia rehi) on a blade of zoysiagrass. Photo Credit: Lyle J. Buss, University of Florida/IFAS
Mealybugs
Mealybugs are soft-bodied insects that possess a covering of flocculent, white, waxy filaments. They are about 1/8 inch in length and usually pinkish or yellowish in color. Mealybugs have piercing-sucking mouthparts which they use to siphon fluids from the leaves, stems, and sometimes roots of many ornamental plants. Mealybug damage produces discolored, wilted, and deformed leaves.
Scale and Mealybug Management
Cultural Control – Plant inspection prior to purchase or installation is the first line of defense against a scale or mealybug population. Make sure to inspect the undersides of leaves and plant stems. Infested sections of plants can be pruned and plant material should be cleaned from the planting area and discarded. Also, you can increase air flow and decrease humidity by proper installation and pruning. Over-fertilizing can also increase pest populations.
Larva of a brown lacewing. Credits: Lyle Buss, University of Florida.
Biological Control – Predators, such as ladybugs and green lacewings, are usually present in large enough numbers to suppress scales and mealybugs to a desirable threshold. However, broad-spectrum insecticides and bad weather can reduce predator numbers. Look for signs of predation by inspecting dead scales for jagged holes in their waxy coatings. If predation signs are present, use more selective chemical controls and oils as opposed to broad-spectrum products.
Chemical Control – Timing is everything when it comes to managing scale and mealybug insects. Crawler activity is more pronounced with the flush of new plant growth in the spring. Before application, prune infested plant parts off first to promote greater penetration of insecticides into the foliage. Dormant Oils are often used in the winter to smother scale insects. These are good choices to implement because they don’t harm non-target or beneficial insects. Care must be taken to read the label and use them at the correct temperature, since use in hot weather may burn foliage. Contact products (acephate, bifenthrin, carbaryl, etc.) must be applied to inhibit the crawler stages of these insects and systemic products (acetamiprid, imidacloprid, thiamethoxam, etc.) can be used on the sessile growth stage. Plants should be sprayed thoroughly to the point of drip or “run off” from leaves, twigs, and stems. Repeated applications may still be necessary even if the timing is right, as crawler populations are often large and crawlers like to hide under old waxy scales. Systemic drenches are also a viable option. With good spray coverage, horticultural oils can kill scales at all stages of growth. Refer to the product label for phytotoxicity and temperature guidelines. Even after successful treatment, the outer coatings of the scales may remain on the plant material for weeks, which can be unsightly. The best way to determine if scales are dead is to squeeze them. They will be dry when squeezed if they are dead and they will ooze liquids if they are living (they were at least alive to the point of being squashed).
For insect identification and additional information on scale control, please see:
“Here we go ‘round the mulberry bush” is still sung by small children today. There are lots of different versions of the lyrics. But each usually describes a daily or weekly task list. In fact, the rhyme began in 1840 as a cadence for female prisoners exercising at the Wakefield Prison in England. There happened to be a Black Mulberry (Morus nigra) growing in the yard. Black Mulberry is a slow-growing short tree, so as a young tree it appears bushy.
Red Mulberry (Morus rubra) is the native Florida species. It tends to grow more upright, but is still a small tree. Additionally, there are White (Morus alba) and Pakistan (Morus macroura) , as well as, many hybrid Mulberries that will grow in the Florida panhandle. White Mulberry is a fast growing tall tree that is so aggressive that it is classified as an invasive species. It can rapidly seed natural areas and become the dominant species. But, the Pakistan Mulberry is a small tree that develops a characteristic crooked, gnarled trunk and a large fruit. It can be pruned as a bush easily.
Growing the mulberry bush can add a unique winter feature to the landscape while producing food for the birds. Yet, the plant is short enough that the fruit can be harvested without having to shake the tree and gather up the fruit from the ground before the birds get all the berries.
Mulberries are self-pollinating and only require about 400 chill hours. A chill hour is each hour that the temperature remain between 32 and 45 degrees Fahrenheit. After 400 cumulative hours the plant is able to flower. The fruit matures in the late spring to early summer. The birds will be sure to notify everyone when it’s time. Pakistan Mulberry can produce 4 inch long berries.
Mulberries will perform well if planted this winter. Plan on pruning them back each year if the bush effect is desired. It can take a year or two to get fully rooted. Don’t be surprised to see some fruit drop off prematurely as the tree/bush gets established. Also, pay attention to where the mulberry is installed. Windy spots will knock off fruit. What birds eat, they deposit. Mulberries will stain the surfaces they land on. If the fruit is walked through, the staining can be moved to indoor surfaces.
When picking fruit don’t forget the gloves unless dark stained fingers is the new look you’re trying to create.
Until plans were underway for our UF/IFAS Demonstration Butterfly Garden, I had never heard of Cutleaf Coneflower, Rudbeckia lacineata. Master Gardener Volunteer Jody Wood-Putnam included this gem in her garden design and introduced me and many of our visitors to a new garden favorite.
Although in the same genus as your common Black-eyed Susan’s (Rudbeckia fulgida or R. hirta) this perennial has very distinct differences. Rather than the low growing, hairy, oblong leaves of Black-eyed Susan, Cutleaf Coneflower has smooth pinnately lobed leaves with serrated edges. The leaves are still clump forming but form an almost bush-like shape. By mid to late summer, tall flower spikes emerge and are covered in bright yellow flowers bringing the overall height of the plant over 5 feet tall!
Cutleaf Coneflower is native to North America with several variations adapted to different regions including the Southeast and Florida. This perennial performs well in full sun to part shade and needs a lot of space. Mature plants can reach 3’ wide by 10’ tall and may require staking. The plant can spread through underground runners, so be sure to give it lots of space. In North Florida leaves may be evergreen if winter is mild. Cutleaf Coneflower is a good wildlife attractant providing nectar and pollen for many insects and if you leave the flowers on to mature the seed the is eaten by songbirds, including goldfinch.
To see this plant in person, stop by the UF/IFAS Demonstration Garden at 2728 E. 14th Street, Panama City, FL. If during normal business hours, check in for available seeds from our Pollinator Garden. 850-784-6105
Ripening thornless blackberries. Photo credit: Mary Salinas, UF/IFAS Extension.
To everyone’s delight, the blackberries are ripening in the Santa Rosa County Extension demonstration garden. The blackberry patch is a reliable perennial that continues to provide fresh berries year after year. Before you decide against them because you don’t want a thorny and painful hazard in your landscape, remember that there are thornless blackberry cultivars with fruit just as tasty as the old-fashioned thorny blackberry varieties. However, it is important to take care and make sure that the variety or cultivar you choose is adapted to our Florida climate and chill hours.
Blackberries bloom and produce fruit on last year’s canes. This year’s growth (the bright green shoot in the front center) will produce next year. Photo credit: Mary Salinas, UF/IFAS Extension.
You can choose a blackberry variety from your local nursery or propagate some plants from a favorite blackberry grown by a friend or neighbor (with permission, of course). Methods of propagation include stem cuttings, root cuttings, tip layering and removing the suckers that arise from the roots.
Plant when the weather is cooler in winter and choose a sunny spot with good soil. Frequent irrigation is crucial during the establishment period and when the fruit is produced. Weed control with organic or plastic mulches is also important to the success of your blackberry patch.
For more information on blackberry cultivars, propagation and growing success please see the University of Florida publication The Blackberry.
Wildflowers near Live Oak, Florida. Image Credit, UF / IFAS
Florida (“land of flowers” in Spanish) is and has always been full of flowers, and countless civic and public organizations work diligently to protect and promote the beauty of our natural ecosystems. Did you know that the Florida Wildflower Foundation works with the Florida Department of Transportation (FDOT) to preserve wildflower areas on state-maintained roads throughout Florida? This effort really took off in the 1960’s when non-native Crimson clover started sprouting among sod planted by the state FDOT, and has grown into a much larger statewide initiative. The state wildflower license plate program provides funding for these efforts.
Wildflower areas along highways not only improve beauty on the roadsides, but provide habitat for countless pollinator insects that drive our $1.2 billion (annual) citrus and agricultural industries and our own backyard landscapes. In addition, leaving no-mow areas along highways saves money on mowing costs, reduces soil erosion, and improves air quality.
The state wildflower license plate supports wildflower preservation efforts statewide. Photo credit: Florida Wildflower Foundation
Wildflower viewing is typically best in the spring and fall, and particularly in areas (such as state parks and forests) that have been recently managed by prescribed fire. Many low-lying areas are home to beautiful native species such as pitcher plants, hibiscus, and meadowbeauty. Be very careful when viewing or stopping to see roadside wildflowers, and be sure to find designated parking areas to prevent accidents. To find a map of the wildflower trails, visit your local tourism bureau or go online at https://flawildflowers.org/protect/.
Currently, every Panhandle county from Jefferson County east has designated wildflower areas. The Escambia County Board of Commissioners passed a wildflower ordinance supporting the program, and a committee met in May 2019 to determine more areas of the county appropriate to set aside for the program. As opposed to planting new wildflowers, the program prioritizes conserving roadside areas that already support healthy wildflower populations. If you know of good candidates for preservation on state roads in Escambia or any other panhandle county, please contact me (ctsteven@ufl.edu) or Liz Sparks (liz.aparks57@gmail.com) with the Florida Wildflower Foundation.
