by Larry Williams | Apr 23, 2020
One of the things to do while stuck at home due to COVID-19 restrictions, is to look for caterpillars and butterflies in your landscape. I’ve noticed giant swallowtail butterflies (Papilio cresphontes) a little early this year. The giant swallowtail is one of the largest and most beautiful butterflies in our area. Its larval stage is known as the orangedog caterpillar. This unusual name comes from the fact that it feeds on young foliage of citrus trees.
Orangedog caterpillar. Photo credit: Donald Hall, University of Florida
The orangedog caterpillar is mostly brown with some white blotches, resembling bird droppings more than a caterpillar. When disturbed, it may try to scare you off by extruding two orange horns that produce a pungent odor hard to wash off.
I’ve had some minor feeding on citrus trees in my landscape from orangedog caterpillars. But I tolerate them. I’m not growing the citrus to sell. Sure the caterpillars eat a few leaves but my citrus trees have thousands of leaves. New leaves eventually replace the eaten ones. I leave the caterpillars alone. They eat a few leaves, develop into chrysalises and then emerge as beautiful giant swallowtail butterflies. The whole experience is a great life lesson for my two teenagers. And, we get to enjoy beautiful giant swallowtail butterflies flying around in our landscape and still get plenty of fruit from the citrus trees. It is a win, win, win.
In some cases, the caterpillars can cause widespread defoliation of citrus. A few orangedog caterpillars can defoliate small, potted citrus trees. Where you cannot tolerate their feeding habits, remove them from the plant. But consider relocating the caterpillars to another area. In addition to citrus, the orangedog caterpillars will use the herb fennel (Foeniculum vulgare) and rue (Ruta graveolens) as a food source. Some butterfly gardens plant citrus trees to provide food for orangedog caterpillars so that they will have giant swallowtail butterflies. So you could plan ahead and grow some fennel, rue or find a butterfly garden in your area for the purpose of relocating the larvae.
Yellow giant swallowtail butterfly on pink garden phlox flowers. Photo credit: Larry Williams
The adult butterflies feed on nectar from many flowers, including azalea, bougainvillea, Japanese honeysuckle, goldenrod, dame’s rocket, bouncing Bet and swamp milkweed. Some plants in this list might be invasive.
Keep in mind that mature citrus trees can easily withstand the loss of a few leaves. If you find and allow a few orangedog caterpillars to feed on a few leaves of a mature citrus tree in your landscape, you and your neighbors might get to enjoy the spectacular giant swallowtail butterfly.
More information on the giant swallowtail butterfly is available online at http://edis.ifas.ufl.edu/in134.
by Matt Lollar | Apr 23, 2020
I was recently sent some pictures of some unusual growths on pecan tree leaves. At first glance, the growths reminded me of the galls caused by small wasps that lay their eggs on oak leaves. However, after a little searching it became apparent this wasn’t the case. These galls were caused by the feeding of an aphid-like insect known as phylloxera.
Leaf galls caused by pecan phylloxera. Photo Credit: Matt Lollar, University of Florida/IFAS Extension – Santa Rosa County
The feeding from the phylloxera causes the young leaf tissue to become distorted and form a gall that encloses this female insect called a “stem mother”. These insects are rarely seen, but the hatch from over-wintering eggs in March/April just after budbreak. Once hatched, these “stem mothers” crawl to the new leaves and begin feeding. Once the gall forms, they start to lay eggs inside the gall. The eggs hatch inside the gall and the young phylloxera begin to feed inside the gall and the gall enlarges. The matured insects break out of the gall in May and some will crawl to new spots on the leaves to feed and produce more galls.
Pecan stem damage from phylloxera. Photo Credit: University of Georgia
There are two common species of phylloxera that infect the leaves. The Pecan Leaf Phylloxera seems to prefer young trees and the Southern Pecan Leaf Phylloxera prefers older trees. The damage from each of these insects is nearly indistinguishable. Damage from these insects is usually not severe and merely an aesthetic issue.
Once the damage is discovered on a tree, it is too late to control the current year’s infestation. There are currently no effective methods for control of phylloxera in home gardens. Soil drench applications witha product containing imidacloprid have been limited in their effectiveness.
by KR Woodburn | Jan 31, 2020
2020 High Tunnel Workshop
March 21, 2020
Agenda
- 9 A.M. Welcome
Mrs. Vonda Richardson, FAMU Extension, Director
- 9:10 High Tunnels: Site and Crop Selection Considerations for High Tunnels
Dr. Alex Bolques, FAMU Extension/REC – Utilizing Floating Row Covers to Exclude Insect Pests and Increase
Winter Protection in High Tunnels – Ms. Kenda Woodburn, FAMU Extension Agent, Gadsden County
- 9:30 Integrated Management Practices for High Tunnel Organic Vegetable
Production -Dr. Xin Zhao, UF Horticultural Sciences
Hot Pepper, Strawberry, and Leafy Green Production in Protective
Structures -Dr. Gilbert Queeley and Alex Bolques, FAMU Extension
- 10:20 Break
- 10:30 Monitoring and Management of Pest and Beneficial Insects in the High Tunnel Production Systems – Dr. Muhammad Haseeb, FAMU Center for Biological Control
- Cultural Management of Insect Pests: Plant-mediated Push-Pull Technology – Dr. Susie Legaspi, ARS Research Entomologist
- 11:20 Field Demonstration: Protected Ag
- Short walk to high tunnel areas
– Leafy greens production using organic methods
– Sustainable strawberry production using organic methods
– Low cost high tunnel structural improvements
– Strawberry season extension
– Selective vegetable hydroponic production systems
- 12:30 Lunch and Learn:
High Tunnel Cost Sharing Opportunities
Mrs. Karyn Ruiz-Toro, NRCS District Conservationist
Resources & Supplies for High Tunnel Growers
Ms. Kenda Woodburn, FAMU Extension
1 P.M. Adjourn
by Matt Lollar | Dec 10, 2019
Loquat trees provide nice fall color with creamy yellow buds and white flowers on their long terminal panicles. These small (20 to 35 ft. tall) evergreen trees are native to China and first appeared in Southern landscapes in the late 19th Century. They are grown commercially in subtropical and Mediterranean areas of the world and small production acreage can be found in California. They are cold tolerant down to temperatures of 8 degrees Fahrenheit, but they will drop their flowers or fruit if temperatures dip below 27 degrees Fahrenheit.
A beautiful loquat specimen at the UF/IFAS Extension at Santa Rosa County. Photo Credit: Matt Lollar, University of Florida/IFAS – Santa Rosa County
Leaves – The leaf configuration on loquat trees is classified as whorled. The leaf shape is lanceolate and the color is dark green with a nice soft brown surface underneath. These features help give the trees their tropical appearance.
Flowers – 30 to 100 flowers can be present on each terminal panicle. Individual flowers are roughly half an inch in diameter and have white petals.
Fruit – What surprises most people is that loquats are more closely related to apples and peaches than any tropical fruit. Fruit are classified as pomes and appear in clusters ranging from 4 to 30 depending on variety and fruit size. They are rounded to ovate in shape and are usually between 1.5 and 3 inches in length. Fruit are light yellow to orange in color and contain one to many seeds.
A cluster of loquat flowers/buds being pollinated by a honey bee. Photo Credit: Matt Lollar, University of Florida/IFAS – Santa Rosa County
Propagation – Loquat trees are easily propagated by seed, as you will notice as soon as your tree first bears fruit. Seedlings pop up throughout yards containing even just one loquat tree. It is important to note that the trees do not come true from seed and they go through a 6- to 8-year juvenile period before flowering and fruiting. Propagation by cuttings or air layering is more difficult but rewarding, because vegitatively-propagated trees bear fruit within two years of planting. Sometimes mature trees are top-worked (grafted at the terminal ends of branches) to produce a more desirable fruit cultivar.
Loquat trees are hardy, provide an aesthetic focal point to the landscape, and produce a tasty fruit. For more information on growing loquats and a comprehensive list of cultivars, please visit the UF EDIS Publication: Loquat Growing in the Florida Home Landscape.
by Sheila Dunning | Dec 4, 2019
“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.
For more information on mulberries: http://gardeningsolutions.ifas.ufl.edu/plants/trees-and-shrubs/trees/mulberry.html
by Matt Lollar | Oct 8, 2019
Last week at the Panhandle Fruit and Vegetable Conference, Dr. Ali Sarkhosh presented on growing pomegranate in Florida. The pomegranate (Punica granatum) is native to central Asia. The fruit made its way to North America in the 16th century. Given their origin, it makes sense that fruit quality is best in regions with cool winters and hot, dry summers (Mediterranean climate). In the United States, the majority of pomegranates are grown in California. However, the University of Florida, with the help of Dr. Sarkhosh, is conducting research trials to find out which varieties do best in our state.
In the wild, pomegranate plants are dense, bushy shrubs growing between 6-12 feet tall with thorny branches. In the garden, they can be trained as small single trunk trees from 12-20 feet tall or as slightly shorter multi-trunk (3 to 5 trunks) trees. Pomegranate plants have beautiful flowers and can be utilized as ornamentals that also bear fruit. In fact, there are a number of varieties on the market for their aesthetics alone. Pomegranate leaves are glossy, dark green, and small. Blooms range from orange to red (about 2 inches in diameter) with crinkled petals and lots of stamens. The fruit can be yellow, deep red, or any color in between depending on variety. The fruit are round with a diameter from 2 to 5 inches.
Fruit, aril, and juice characteristics of four pomegranate cultivars grown in Florida; fruit harvested in August 2018. a) ‘Vkusnyi’, b) ‘Crab’, c) ‘Mack Glass’, d) ‘Ever Sweet’. Photo Credit: Ali Sarkhosh, University of Florida/IFAS
A common commercial variety, ‘Wonderful’, is widely grown in California but does not perform well in Florida’s hot and humid climate. Cultivars that have performed well in Florida include: ‘Vkusnyi’; ‘Crab’; ‘Mack Glass’; and ‘Ever Sweet’. Pomegranates are adapted to many soil types from sands to clays, however yields are lower on sandy soils and fruit color is poor on clay soils. They produce best on well-drained soils with a pH range from 5.5 to 7.0. The plants should be irrigated every 7 to 10 days if a significant rain event doesn’t occur. Flavor and fruit quality are increased when irrigation is gradually reduced during fruit maturation. Pomegranates are tolerant of some flooding, but sudden changes to irrigation amounts or timing may cause fruit to split.
Two pomegranate training systems: single trunk on the left and multi-trunk on the right. Photo Credit: Ali Sarkhosh, University of Florida/IFAS
Pomegranates establish best when planted in late winter or early spring (February – March). If you plan to grow them as a hedge (shrub form), space plants 6 to 9 feet apart to allow for suckers to fill the void between plants. If you plan to plant a single tree or a few trees then space the plants at least 15 feet apart. If a tree form is desired, then suckers will need to be removed frequently. Some fruit will need to be thinned each year to reduce the chances of branches breaking from heavy fruit weight.
Anthracnose caused by Colletotrichum sp. to pomegranate fruit. Photo Credit: Gary Vallad, University of Florida/IFAS
Anthracnose is the most common disease of pomegranates. Symptoms include small, circular, reddish-brown spots (0.25 inch diameter) on leaves, stems, flowers, and fruit. Copper fungicide applications can greatly reduce disease damage. Common insects include scales and mites. Sulfur dust can be used for mite control and horticultural oil can be used to control scales.
