by Sheila Dunning | May 25, 2017
As oak trees are now fully leafing out and people start hanging out in the shade of the canopy, many of you are noticing strange growths on the branches. They look like potatoes, spiky cones and fuzz balls on the leaves and stems. Don’t worry. It’s just a harmless wasp that chose that tree to create a nursery for her young.
Galls are abnormal plant growth or swellings comprised of plant tissue. Galls are usually found on foliage or twigs. These unusual deformities are caused by plant growth-regulating chemicals produced by tiny wasps. The chemicals produced by these insects interfere with normal plant cell growth.
The life cycles of the various gall-forming wasps are highly variable. Two or more years are required for gall wasps that develop in woody twig galls to reach maturity. Gall-forming wasps usually overwinter as adults in protected places away from the host tree. As the buds break in the spring and the leaves begin to expand, these small wasps start to lay their eggs in expanding plant tissue. During the egg-laying process or early larval-feeding period, specialized body glands secrete growth-regulating chemicals that interact with certain plant chemicals to produce these abnormal growths.
After a brief period of cell growth, gall development stops completely. Once these galls are formed, they do not continue to use nutrients from the host plant. The insect is confined within “its house” and feeds only on gall tissue during the remainder of its development. The galls provide shelter, protection, and food for the immature wasps. Inside a gall, the larvae are surrounded by tissues rich in nutrients
There are a variety of gall-forming species of small wasps that commonly infest oak, Quercus spp ., trees. Galls generally are aesthetically objectionable to homeowners who find them unattractive and fear that galls will cause damage to the health of their oak trees. Most leaf galls on oak cause little or no harm to the health of a tree. However, twig or branch galls may cause injury by distorting branch development in a heavily infested tree.
Chemical control is seldom suggested for management of leaf galls on oak. Cultural methods of control may be effective in reducing the impact of these insects. Some fallen leaves may harbor various life stages of gall-producing pests. Therefore, it may be useful to collect and destroy all infested leaves. Some of these pests overwinter in twigs and branches of oak. Where such woody galls are detected, prune and destroy the infested plant material when the galls are small and have just started to develop. But, remember every bug needs a home!
All photos by Eileen Buss, UF Entomologist
by Daniel J. Leonard | May 18, 2017
If you’re like me, growing turfgrass is often more of a hassle than anything else. Regardless of the species you plant, none tolerates shade well and it can seem like there is a never-ending list of chores and expenses that accompany lawn grass: mowing (at least one a week during the summer), fertilizing, and constantly battling weeds, disease and bugs. Wouldn’t it be nice if there were an acceptable alternative, at least for the parts of the lawn that get a little less foot traffic or are shady? Turns out there is! Enter the wonderful world of perennial groundcovers!
Perennial groundcovers are just that, plants that are either evergreen or herbaceous (killed to the ground by frost, similar to turfgrass) and are aggressive enough to cover the ground quickly. Once established, these solid masses of stylish, easy to grow plants serve many of the same functions traditional turf lawns do without all the hassle: choke out weeds, provide pleasing aesthetics, reduce erosion and runoff, and provide a habitat for beneficial insects and wildlife.
The two most common turfgrass replacements found in Northwest Florida are Ornamental Perennial Peanut (Arachis glabra) and Asiatic Jasmine (Trachelospermum asiaticum); though a native species of Mimosa (Mimosa strigillosa) is gaining popularity also. All of these plants are outstanding groundcovers but each fills a specific niche in the landscape.
Perennial Peanut Lawn
Perennial Peanut is a beautiful, aggressive groundcover that spreads through underground rhizomes and possesses showy yellow flowers throughout the year; the show stops only in the coldest winters when the plant is burned back to the ground by frost. It thrives in sunny, well-drained soils, needs no supplemental irrigation once established and because it is a legume, requires little to no supplemental fertilizer. It even thrives in coastal areas that are subject to periodic salt spray! If Perennial Peanut ever begins to look a little unkempt, a quick mowing at 3-4” will enhance its appearance.
Asiatic Jasmine
Asiatic Jasmine is a superb, vining groundcover option for areas that receive partial to full shade, though it will tolerate full sun. This evergreen plant sports glossy dark green foliage and is extremely aggressive (lending itself to very rapid establishment). Though not as vigorous a climber as its more well-known cousin Confederate Jasmine (Trachelospermum jasminoides), Asiatic Jasmine will eventually begin to slowly climb trees and other structures once it is fully established; this habit is easily controlled with infrequent pruning. Do not look for flowers on this vining groundcover however, as it does not initiate the bloom cycle unless allowed to climb.
Sunshine Mimosa
For those that prefer an all-native landscape, Sunshine Mimosa (Mimosa strigillosa), also known as Sensitive Plant, is a fantastic groundcover option for full-sun situations. This herbaceous perennial is very striking in flower, sending up bright pink, fiber-optic like blooms about 6” above the foliage all summer long! Sunshine Mimosa, like Perennial Peanut, is a legume so fertility needs are very low. It is also exceptionally drought tolerant and thrives in the deepest sands. If there is a dry problem spot in your lawn that receives full sun, you can’t go wrong with this one!
As a rule, the method of establishing groundcovers as turfgrass replacements takes a bit longer than with laying sod, which allows for an “instant” lawn. With groundcovers, sprigging containerized plants is most common as this is how the majority of these species are grown in production nurseries. This process involves planting the containerized sprigs on a grid in the planting area no more than 12” apart. The sprigs may be planted closer together (8”-10”) if more rapid establishment is desired.
During the establishment phase, weed control is critical to ensure proper development of the groundcover. The first step to reduce competitive weeds is to clean the site thoroughly before planting with a non-selective herbicide such as Glyphosate. After planting, grassy weeds may be treated with one of the selective herbicides Fusilade, Poast, Select, or Prism. Unfortunately, there are not any chemical treatments for broadleaf weed control in ornamental groundcovers but these can be managed by mowing or hand pulling and will eventually be choked out by the groundcover.
If you are tired of the turfgrass life and want some relief, try an ornamental groundcover instead! They are low-maintenance, cost effective, and very attractive! Happy gardening and as always, contact your local UF/IFAS County Extension Office for more information about this topic!
by Beth Bolles | Mar 30, 2017
We often talk about sandy, nutrient poor soil in Florida and how difficult it is for growing many favorite landscape plants. Gardeners may spend considerable time and money amending soils with organic matter to improve quality.
The low maintenance approach is to embrace your sandy soil and consider plants that thrive in sandy, well-drained soil. One very attractive native shrub that actually prefers this type of soil is false rosemary, Conrandina canescens.
False rosemary is a member of the mint family that is well adapted to drier, sandy soils. It can be found in many coastal communities growing in natural areas. It is easily recognized in the spring and early summer by light purple blooms. Considered a small shrub or groundcover, False rosemary needs full sun. One plant can easily spread out to 4-5 feet in diameter with a height of 2-3 feet.
False rosemary is an attractive native plant for Gulf Coast landscapes. Photo by Beth Bolles, UF Escambia County Extension
False rosemary does have aromatic foliage and is attractive to bees. It is a very low maintenance plant once established and its few issues tend to be related to soils with too much moisture and plants being shaded after establishment. New seedlings will emerge around the main plant when growing conditions are right. If you want to try this native plant in your landscape, talk to a local nursery.
False rosemary flowers are attractive to pollinators. Photo by Beth Bolles, UF Escambia County Extension
by Mary Salinas | Mar 9, 2017
Dark red flowers of Florida red anise arrive in the springtime. Photo credit: Mary Derrick, UF/IFAS Extension.
Springtime brings small but very pretty red blooms on an outstanding native shrub/small tree, Florida red anise (Illicium floridanum). It occurs naturally in the wild in the central and western panhandle of Florida and west along the gulf coast into Louisiana. Its natural environment is in the understory along streams and in rich, wooded areas.
This is a great shrub for a part shade to shady and moist area in your landscape. The dense foliage, dark green leaves and the fact that it is evergreen all year makes it a great choice for an informal hedge. Plan for it to grow to a maximum height of 12 to 15 feet.
Dense growth habit of Florida red anise. Photo credit: Mary Derrick, UF/IFAS Extension.
The leaves have a licorice-like aroma when crushed but this is NOT the species that gives us the edible culinary anise. Maybe it is that aroma that makes this a relatively pest-free plant!
Yellow anise (Illicium parviflorum) is a very similar native shrub but has small yellow flowers and adapts better to a drier environment. The native range of the yellow anise is north central Florida.
by Larry Williams | Jan 26, 2017
Live oak with immature acorns. Photo credit: Wendy VanDyke Evans, Bugwood.org.
Do you have more acorns than you know what to do with? When oaks produce loads of acorns, it sometimes is called a “mast” year. Do you remember the oak tree pollen and all those catkins that fell from oaks earlier in spring?
Catkins are the male flowers in oaks. Some people refer to them as tassels or worms. The airborne pollen from these catkins were part of the reproductive process in fertilizing the female oak flowers that ultimately resulted in all of these acorns. Oaks produce separate male and female flowers on the same tree. Female flowers in oaks are very small. You’d have to look very close to see them. Many oaks did well in their reproductive efforts this spring. Acorns are oak seeds. This entire process is part of the cycle of life.
There are theories about mast years, wildlife’s use of these acorns and what gardeners can expect next year as a result of this year’s abundant acorn crop. Timing of mast years is still a mystery. Numerous theories exist ranging from weather to geography to the life cycles of predators.
The most likely reason for high production seems to be weather-related. When oak trees have favorable weather at the time of oak flowering and good growing conditions, the mast seems to be increased.
But mast years happen irregularly, making it difficult to understand what causes a mast year. Heavy acorn production can occur twice in a row or it might be separated by several years or more. There’s no good way to predict it.
Mast years are important to wildlife, as acorns are an important food for many animal species. In low crop years, birthrate for some wildlife species, such as squirrels, will decline the following year. This also may involve increased competition for food and survival rates. The recent crop means that more young are likely to be produced by animals that forage for acorns.
Wildlife play a big role in forest regeneration. When acorns drop out of oaks, many animals help distribute these seeds. Squirrels can bury hundreds of acorns. Some of these acorns germinate and grow to become the next generation of oak trees. Some will be eaten by birds, bears, deer, rodents, including squirrels, and other wildlife. Rodents are in turn eaten by carnivores and deer browsing shapes which kinds of plants become established and survive. All those acorns have far-reaching impact on wildlife and our forests.
So, try to keep this in mind as you are fussing with all those acorns in your lawn and landscape this season.
by Julie McConnell | Jan 17, 2017
Winter flowers and small leaves with serrated edges lead to identification as Camellia sasanqua. Photo: J_McConnell, UF/IFAS
A common diagnostic service offered at your local UF/IFAS Extension office is plant identification. Whether you need a persistent weed identified so you can implement a management program or you need to identify an ornamental plant and get care recommendations, we can help!
In the past, we were reliant on people to bring a sample to the office or schedule a site visit, neither of which is very practical in today’s busy world. With the recent widespread availability of digital photography, even the least technology savvy person can usually email photos themselves or they have a friend or family member who can assist.
If you need to send pictures to a volunteer or extension agent it’s important that you are able to capture the features that are key to proper identification. Here are some guidelines you can use to ensure you gather the information we need to help you.
Entire plant – seeing the size, shape, and growth habit (upright, trailing, vining, etc.) is a great place to begin. This will help us eliminate whole categories of plants and know where to start.
Stems/trunks – to many observers stems all look the same, but to someone familiar with plant anatomy telltale features such as raised lenticels, thorns, wings, or exfoliating bark can be very useful. Even if it doesn’t look unique to you, please be sure to send a picture of stems and the trunk.
Leaves – leaf color, size and shape is important, but also how the leaves are attached to the stem is a critical identification feature. There are many plants that have ½ inch long dark green leaves, but the way they are arranged, leaf margin (edges), and vein patterns are all used to confirm identification. Take several leaf photos including at least one with some type of item for scale such as a small ruler or a common object like a coin or ballpoint pen; this helps us determine size. Take a picture that shows how leaves are attached to stems – being able to see if leaves are in pairs, staggered, or whorled around a stem is also important. Flip the leaf over and take a picture of the underside, some plants have distinctive veins or hairs on the bottom surface that may not be visible in a picture taken from above.
Flowers – if flowers are present, include overall picture so the viewer can see where it is located within the plant canopy along with a picture close enough to show structure.
Fruit – fruit are also good identification pictures and these should accompany something for scale to help estimate size.
Any additional information you are able to provide can help – if the plant is not flowering but you remember that it has white, fragrant flowers in June, make sure to include that in your description.
Learning what plants you have in your landscape will help you use your time and resources more efficiently in caring for you yard. Contact your local UF/IFAS Extension office to find out who to send requests for plant id.
As oak trees are now fully leafing out and people start hanging out in the shade of the canopy, many of you are noticing strange growths on the branches. They look like potatoes, spiky cones and fuzz balls on the leaves and stems. Don’t worry. It’s just a harmless wasp that chose that tree to create a nursery for her young.
