Each year in the fall you may notice tent-like webs in hardwood trees with dead or stripped foliage inside. These unsightly webs and foliage damage are caused by a common forest insect in our area, the fall web worm. These are the caterpillar phase of a native moth which tend to cause varying degrees of damage to tree foliage each year. Luckily, the caterpillars’ defoliation is usually late in summer to fall when the leaves are beginning to go dormant in hardwoods. Since the trees have stored most of the energy they need for the winter dormant period the defoliation fall web worms cause is usually not a problem especially on mature trees. Nonetheless the webs are often unsightly and in severe outbreak years they may completely defoliate some trees, particularly smaller and newly established trees. They can be controlled to some degree and luckily bad outbreaks are few and far between. Mostly fall web worms become a problem in home landscapes, orchards, and urban settings. In forests they tend not to cause significant damage but are noticeable due to the tentlike webs. In recent tree plantings for wildlife, they can be problematic by stripping the foliage on the trees.
Here in the Panhandle there can be several generation in a year, and as the growing season goes on the population grows. Earlier in the year the webs are smaller and the caterpillars feeding is less noticeable. By fall when the populations get large, the tentlike nests and stripped foliage is very noticeable. The caterpillars are gregarious and aggregate together close to where they hatch. The female moth lays eggs in the late spring in clutches on the underside of leaves. When the eggs hatch the caterpillars group together and start spinning webs out of silk as the young caterpillars skeletonize leaves. As they grow the web nest becomes larger and more foliage is consumed, forming the large unsightly tent nests we notice in the fall. They tend to form the web tent out toward branch tips and several colonies may form on a tree. The caterpillars only feed on foliage inside the web tent and expand they need more fresh foliage to feed on. The web is a natural defense against predators and by forming the tent nest they can feed in relative safety. As temperature cool and fall comes to a close the caterpillars leave the nest to pupate in leaf litter and bark crevices. They overwinter as pupa to become adult moths next spring. The wind and rain over winter usually removes the web nest and the tree puts on new growth next spring with no lasting damage.
Fall Webworms defoliating a persimmon tree Photo Credit: UF IFAS Entomology Department
Mostly webworms and their feeding activity are unsightly, especially in landscape settings. The main issue with fall web worm is when a large number of colonies form on a young tree, which can completely defoliate a tree. Orchards are another setting where large outbreaks of webworms can be an issue. When only a couple of web nests form on a tree control is usually not necessary except from an appearance and aesthetic point of view. Fall web worms have a broad range of host plants and will readily feed on a majority of deciduous hardwood trees and shrubs. They seem to favor pecans, hickories, walnut, and persimmon particularly along with sweetgum, yellow poplar, maples, and oaks to a lesser extent. Fall web worm is a particularly troublesome pest in pecan orchards and home landscape pecans. It is important to watch the extent of webworm infestation in these settings, particularly on younger trees. By the time late fall rolls around though removal of the webs and dead foliage may be helpful, but most trees have gone dormant for the year. On young trees that have had total defoliation this can weaken them during winter dormancy, so some TLC and extra attention in the spring are usually good follow ups.
Luckily since fall web worm is a native species there are plenty of predators, parasitoids, and disease that keep these pesky caterpillars in check. If you have a few fall web worm nests in your landscape there are some simple and effective control methods that can be used. One of the best is to simply destroy the web nests and expose the caterpillars to predators. The webs protect the caterpillars from birds and other predators and are their main defense. By simply taking a pole, tool handle, or other implement to reach the web you can simply tear it open and shake it, predators will help do the rest. Another option is to simply prune out the webbed branch, especially since they tend to be towards the tip. They can then be disposed of and the caterpillars along with them. Using sprays and pesticides are usually not extremely effective. Since the caterpillars are inside the dense web any spray usually cannot penetrate the protective web. Treatment of the foliage around the webs can be effective if applied earlier in the year since active feeding will ensure contact with control treatments. Several insecticidal soaps, horticultural oils, and effective insecticides are available and labeled for fall web worm control. This is only necessary in a severe outbreak and timing is everything. If you wait until mid to late fall most feeding activity has ceased and caterpillars will be beginning to pupate for winter, making pesticides ineffective.
Fall web worm caterpillar in the early stages of development. Photo Credit: UF-IFAS Entomology Department
If you are seeing a bit of fall web worm in your area it likely catches your attention. If you have just a few branch tips affected the issue will likely go away on its own. Unless a tree is being almost completely defoliated this pest is more annoyance than anything, despite the unsightly and noticeable webs. If you are just now noticing an issue it is probably best to just wait and let the annual cycle play out. Fall webworm is an unsightly and annoying annual occurrence in trees but luckily it causes minimal damage and can be easily controlled. It is part of our natural landscapes and forests although it can be unsightly and concerning in years with significant outbreaks. For young or recently planted trees it only becomes an issue if complete defoliation occurs and usually the tree will shake this off and leaf out full next spring. Fall web worm can be noticeable and unsightly, but there is really no cause for concern in most cases. As with most things letting nature take its course and the annual cycle play out is usually the best option.
How are the live oak (Quercus virginiana) and the history of the United States Navy linked? That is a very interesting question that actually led to the first forest reservation and planting project in the United States. That reservation and history is still alive and well here in the Florida Panhandle, preserved still today as the Naval Live Oaks area of Gulf Islands National Seashore. In our modern times it may not register what forest and wood resources had to do with national defense but in the 1700’s and 1800’s it was key. In the times of wooden sailing ships having a Navy was key to being a Great Power. To have a powerful navy a nation had to have wood and shipbuilding resources, which meant access to forests. The abundant forest resources of North America were a driving force for colonization, especially for the British. Building the Royal Navy into the most powerful at the time required a huge amount of resources, which the American Colonies had in abundance. When our nation won its independence, it was similarly a major asset for the United States as the U.S. Navy was built. The U.S. government quickly recognized that these resource needed to be maintained and reserved, particularly the live oak which was a major wood resource with a limited supply. This led to the first forest conservation measure, which was the establishment of Naval Live Oak Reservations along the Gulf Coast in the early 1800’s.
View from a high sand hill in Naval Live Oaks Gulf Breeze, FL Photo Credit: Ian Stone
Building sailing ships, required resources for the hull, masts, and waterproofing which all came from different trees and forest resources. Mast trees were in particularly high demand and usually were from particularly large and straight pines or spruce. This was a limited resource and the Eastern white pine (Pinus strobus) was a particularly good resource in North America. The southern pines were highly prized for production of naval stores which consisted of turpentine, tar, and rosin used for maintaining and waterproofing ships and their rigging. Oak was prized for hull construction, a live oak above the others. Live oak is exceeding strong and dense, one of the densest woods in North America. If you have ever experienced trying to split live oak for firewood you likely realize how hard it truly is. Axes and splitting wedges will bounce right off and barely crack a solid live oak log. It also grows in such a way that it was perfect for constructing the braces and complex hull components of ships. With these forest resources the United States had what it needed to begin building the United States Navy, a key component of national defense. In the War of 1812, the need for a strong Navy became readily apparent, and the U.S.S. Constitution would gain fame in its engagement with the Royal Navy on the open seas. U.S.S Constitution would get the nick name “Old Ironsides” from her strong live oak hull which appeared impervious to cannon shots during engagements. It is no wonder that the live oak resource was soon recognized as a critical need in expanding the Navy. President John Quincy Adams established the Naval Live Oak Reservation Program and in 1828 the Naval Live Oak Reservation was established in what is today Gulf Breeze, FL. Under the Department of the Navy a tree planting effort establishing young live oaks by planting acorns was established in the reserve. This made the Naval Live Oaks Reservation the first forestry preserve and one of the first managed forests in the United States. As with so many things it was national defense and the armed forces need for resources that lead to this program and reservation.
As live oak is a strictly North American species by the 1830’s the United States had near total control over this valuable resource. To ensure the resource was properly managed and not exhausted the Naval Live Oak Reservation system remained in place for nearly a century, with other reservations established along key areas along the Gulf and Atlantic Coasts. During this period almost all of the most significant live oak groves and resource was under Federal control for use in the building of naval ships. During the period through the civil war and just beyond this remained a critical resource for maintain Naval Power. By the start of the 20th century though wooden sailing ships had given way to steel steamers, and the live oak resource was no longer critical. In the early 1900’s many of the Naval Live Oak Reservations were returned to local governments, but the Naval Live Oaks remained in federal control. When the Gulf Islands National Seashore was created in 1971 it became part of that park under the National Park Service.
View of the Shoreline along the Naval Live Oaks Photo Credit: Ian Stone
Today you can go visit the Naval Live Oaks and experience the rich history as well as the pine and live oak forests that are part of the site. Unless you have done some history research or read some of the informational displays at the reservation the name may have been a bit puzzling. Today the forest resources at the Naval Live Oaks Reservation are not essential to our national defense. Live oak is now seldom used in lumber or other wood product applications and is largely ignored as a timber species. Today we can cherish this forest reservation for its conservation resources and the forest it preserves in an area that is heavily developed. It is a beautiful place to visit and hike, with a wonderful trail network both along the sandy hills and shorelines. You will need to have a Gulf Islands National Seashore pass as it is a fee area. It is well worth a visit to enjoy a unique forest ecosystem, which is truly unique historically. The natural beauty and habitat that the preserve covers are all due to the live oaks’ unique use in ship building during the age of sail. The live oak is a cherished and iconic tree in our region for many reasons, but when you visit the Naval Live Oaks consider the role it played in the development of the mighty United States Navy and our nation’s sea power in the era of wooden ships. While the original reason for the Naval Live Oak Reservation has past it still stands as a testament to the importance of forest resources to our nation nearly 200 years after it was founded.
Thinning is an important part of any forest management plan and getting it right can be the difference between successful outcomes and persistent problems. Probably one of the most common questions foresters get is “Should I Thin My Trees?”. It is an important question to ask and definitely needs a forester’s input to get right. Thinning is part of managing the density of a forest stand and preventing issues with overstocking. If a stand is overstocked it causes multiple issues with the health and growth of a forest stand. Forest stands can even stunt when left in overstocked conditions and fail to produce the timber yield that would be expected. Not thinning at proper intervals when it is needed also results in lost growth even if the thinning is performed later. The key issue is competition and managing density prevents excessive competition among trees. To understand how thinning works you must understand some of how trees grow.
An overstocked pine stand in need of thinning Santa Rosa County, FL . Photo Credit: Ian Stone
Trees compete on a site for resources such as sunlight, water, and nutrients. As a young stand of timber develops the trees initially have plenty of resources while they are young and small, but they begin to compete when they grow older. Initially the competition can be a good thing encouraging taller and straighter growth habits and self-pruning of lower branches. As the stand develops though the competition becomes a negative factor when the trees begin to experience stress from lack of resources, primarily sunlight but also nutrients and water. At this point the stand is considered overstocked and thinning will improve the health and growth of the trees. Effectively thinning removes trees that are not needed and will eventually be out-competed and die. This allows a landowner to make some timber revenue while improving growth and health down the road. The trees that remain after thinning no longer are overstocked and competing and respond with improved growth and health. This important forest management technique is one of the primary management decisions in timberland ownership.
Overstocked stands create multiple issues that cause negative outcomes. One of the primary issues is that trees in overstocked conditions are weaker and more susceptible to insect and disease outbreaks. It is very common for bark beetle outbreaks and other issues to take hold in overstocked stands and produce considerable losses. Thinning is an effective measure at preventing this. Overstocked conditions result in poor growth and can lead to a situation where trees have a low portion of living foliage. Once this occurs a stand can become locked in a slow growing condition that can’t be reversed. This causes a loss of both volume and quality by reducing the development of high value saw-timber and poles. Overstocked and dense stands are also less desirable for wildlife and plant diversity. Thinning opens up the forest and allows more light and space which improves habitat and increases diversity on the forest floor and lower levels. All around thinning at the right time based on the forest conditions and stocking produces better outcomes. During thinning trees with form, disease, or other issues can be removed to improve the overall stand. Determining when and how to thin is a function of having a good forest inventory and monitoring tree size and stocking. There is usually a period of time that is referred to as a “thinning window” when the stand is beginning to become overstocked but will still produce a thinning response. This varies based on forest conditions and is more of a function of the size and density of the trees than an exact age or predetermined point in time. The best practice is to determine when a forest is entering the thinning window and take advantage of the thinning benefits. Delaying thinning will result in less optimal outcomes and results may be permanent. Similarly thinning too early or thinning incorrectly (too few or too many trees removed) can produce less desirable results. The key is to thin correctly and thin when forest conditions indicate it is needed.
Overall thinning is one of the best forest improvement practices available, and to get the most benefit it has to be done correctly. Far too often forest areas that need thinning are overlooked and go far too long without getting the thinning they need. You do not want to look into getting your timber thinned only to find out you should have done it 5-8 years ago or more. Worse still you develop a southern pine beetle out break and loose timber or start to have timber die from competition. The best way to make sure you stay informed on when and to what extent to thin is to have a forest management plan and update it regularly. Working with a consulting forester to inventory your timber stand and plan out forest management is one of the best things you can do. A good consultant forester can assist you in determining when and how to thin properly. They can also assist in marketing timber harvested in a thinning along with other services like timber marking. You can get assistance through the County Forester office with Florida Forest Service as well. You can work with the County Forester to enroll in the Forest Stewardship Program and get a management plan written at no cost to you. A forest management plan will cover thinning and other important practices to help you meet your goals. Determining when and how to thin is something that requires advice from a good professional forester. By working with a professional forester, you will avoid common pitfalls like making opportunistic thinning decisions, over-thinning, under thinning, leaving poor quality trees, and more. If you think your stand may need thinning contact the extension office, the county forester, or a professional forester of your choice. Making those contacts are a great first step in getting the most out of a good thinning.
Silvopasture is a unique and highly effective agroforestry technique that can be a great fit to accomplish some landowners’ land management and agricultural enterprise objectives. Agroforestry is a system which combines forest management and agricultural production systems to get synergistic effects that make both systems more sustainable and resilient. While these systems do not seek to optimize and maximize forestry or agricultural outputs the overall economic and total outputs are usually higher than stand alone traditional or forestry systems. They are also very ancient and many of the worlds oldest agricultural systems and methods would fall under the agroforestry umbrella now. Silvopasture is one unique expression of this method of combining forestry and agriculture. Silvopasture systems seek to combine forestry, forage production, and livestock on one area of land where all three combined make for a strong system of both shorter term agricultural production and longer term forest products production. For the right landowner and the right objectives it can be a perfect match.
Are you and your landholdings suited to Silvopasture? The best way to find out is consult with our outstanding extension agents and visit an outstanding Silvopasture system and producer to see it in the field. Fortunately, this month just this opportunity will be provided in Washington County at the extension office in Chipley, FL. The morning will feature a series of presentations and a discussion panel covering forestry, forage production, soil consideration, and livestock components of silvopasture systems. The presenters will consist of agents Ian Stone (Forestry Walton/ Multi-county), Mark Mauldin (Agriculture, Washington), Jenifer Bearden (Agriculture, Okaloosa), Nick Simmons (Agriculture, Escambia). The morning session will be followed by a catered lunch. For the afternoon the program will feature an outstanding tour of an advanced and well established silvopasture system, Mr. George C. Owens is a nationally recognized livestock producer and landowner who has successfully implemented silvopasture systems using a variety of methods. He has presented at conferences at the local, state, and national levels and is an outspoken advocate of silvopasture and sharing his knowledge and agricultural success his lands in silvopasture have produced. The tour will include the panel of agents for infield discussions and questions. UF-IFAS is very grateful to Mr. Owens for opening his property for this tour. The workshop is also approved for 4.5 Category 1 Continuing Forestry Education (CFE) credits for foresters and land managers needing continuing education. The program is part of the Florida Land Steward series for the year and the entire team looks forward to hosting landowners and land managers in from across the Panhandle at this event.
For more information please contact Ian Stone at the Walton Extension Office. Online registration will be through Eventbrite at the following link https://www.eventbrite.com/e/florida-land-steward-silvopasture-101-and-george-c-owens-property-tour-tickets-876970992847?aff=ebdssbdestsearch . Online registration is required and the registration deadline is April 19th. Tickets are limited so please register early to ensure you have a ticket for the event. The team hopes to see those interested on April 26th and looks forward to showcasing how silvopasture can be part of your land management to meet your objectives. Mark your calendars and register early to ensure you can attend this educational and field tour opportunity.
It is Florida Arbor Day and all across the state people will be picking up trees and planting them for the future. It is also the time of year where large reforestation efforts are underway to get the next generation established. Planting trees is one of the most hopeful activities you can do. It takes a long time for a tiny forest seedling to become a titan of the forest. Similarly, a larger nursery grown tree planted in an urban setting takes a long time to get to the large shade tree that is envisioned. Whether in an urban or forest setting getting tree planting right is the difference between success and failure. Today we celebrate Florida Arbor Day, in large part because this is the best time of year to plant trees in our climate. Planting trees in the cold of winter means they can focus on growing and establishing a root system before the leaf and shoot growth they put on in spring. This is why states move their Arbor Day observance and the most southern and warm states like Florida, Louisiana, and Texas have the earliest celebrations.
So, what goes into planting a tree properly? Well, it is a lot more than green side up that is for sure. It takes lots of planning, care, and attention to detail. The specifics are very different when planting thousands of forest seedlings across a tract vs just a few large trees in a park. The basic principles are the same though and we will start with forest trees. For reforestation in forests the journey starts in specialized forest nurseries that produce the millions of trees needed to serve the forest industry of the area. Let’s take a deeper dive into getting tree planting right in this important time of year.
Tree Planting Tips in Forested Settings
Getting tree planting right in forest settings really starts with the tree species and seedlings used. If this is selected wrong, the seedling quality is low, and the seedlings are not handled correctly in shipment and the field; complete planting failures can occur. A failure is very costly as you not only have the cost for this year but the replanting cost the next, plus you lost a year of forest growth. Thankfully, it is very rare now since we know good planting protocols and follow them regularly. Forest seedling nurseries are extremely high tech operations and now provide the best seedlings in the world here in the U.S. The U.S. reforestation system is the envy of the world and the Southeast is the jewel in that crown routinely planting the highest amount of trees of any timber region globally. Entire research divisions at major universities plus state forest agency reforestation sections and the U.S. Forest Service Reforestation Division all work in concert to ensure our forests’ future. That is not to mention the massive private nurseries run by top flight companies that are experts in reforestation and forest management. Landowners and others planting trees now have the best access and reforestation material ever available in private hands, and companies provide the highest quality seedlings available in terms of seedling quality and improved tree genetics. By spending a bit more in reforestation a huge return can be generated when a stand is mature. Landowners can take advantage of this outstanding leap in reforestation technology, but old-fashioned due diligence and good planting technique is key to realize the outcome. First and foremost, the right tree species has to be matched with the right site and range of conditions where it will thrive. Off-site plantings that are not compatible with that species (such as loblolly pine on sandhills) may succeed from a survival standpoint only to fail long term (i.e. stunting and lack of volume development). Care of the seedlings during the planting operation is key to success and establishment though. Seedlings must be stored and cared for properly until planting is completed. Poor techniques will cause issues with root structure and growth and poor care and excessive storage times before planting will cause stress that can result in seedling death or loss of vigor that leads to loss of growth. Plant seedlings right though and you will have an excellent stand. Here are some tips to get tree planting right:
Work closely with a good consulting forester, forest nursery, and or reforestation service provider. Coordinate seedling delivery, storage, and planting well in advance of the operation.
Assess the weather conditions leading up to planting and do not be afraid to cancel if conditions are questionable.
Store seedlings in refrigerated trucks or a refrigerated storage facility (optimal) or tarped in an area that is out of the wind and elements.
Bareroot seedlings are the most sensitive and need to be planted as soon as possible and by skilled crews. Bareroot are prone to J-rooting and other issues if not planted with the correct equipment for the soil conditions and by highly trained and skilled crews. If machine planting ensure test runs are done to make sure the planting trench and packing system are working well and planting seedlings correctly.
Ensure the seedling type and planting conditions are communicated to the crew well ahead of arrival for logistical purposes. A Consulting Forester is invaluable here and results are usually better when a landowner uses a consultant that can coordinate. Issues like planting crews showing up with 4 inch container dibbles (the industry standard) when the landowner has ordered 6 inch containerized seedlings can be a disaster.
Conduct quality control and spacing checks throughout the planting operation to make sure seedlings are in good condition and being planted according to best practices and the planned reforestation operation. Communicate with the crew on changes needed. Crews want to do a good job and usually enjoy working together with the forester or landowner to get the best job done.
Urban Forests
We have passed the forest tree category and we move to the urban forest and what is really the art of individual tree management. Urban forests are very different from natural forests, but they are still forests and the management principles of forestry still apply. The primary difference is planting operations in natural settings involve thousands of trees and usually count on a certain amount of loss. Urban reforestation and tree planting can rely on just a few to several hundred trees depending on the scope. The main difference is urban operations use single large container trees that have been grown for several years in the nursery and will be planted in very specific locations. There is a significant focus on each tree and the investment per tree is huge by comparison. Given this it is highly desirable that each tree live and the expense and investment in each individual tree necessitates this. Urban forests also have ready access to things like irrigation, tailored fertilizer, and many other tree care options to improve establishment. Most Arbor Day activities focus on these urban planting operations and things like tree dedications. To get it right let’s look at what we need to do to get urban trees planted right in our urban forests.
Tree Planting Tips for Urban Areas
Urban trees have a rough life compared to their relatives in the natural forest. Natural forests do not have the myriad of issues that the urban forest does, but that does not mean trees can’t thrive in our urban ecosystem. Here in the Florida Panhandle, we have some of the largest and most densely covered urban forests in our city centers and metropolitan areas. In fact, our urban forest tree cover is some of the highest in the country. This is likely due in large part to our lush semi-tropical forest ecosystem that naturally thrive here. With good management our Urban Forest just sort of forms and towers over our urban landscape. Another factor supporting this is the local community commitment to tree planting and tree care. The vast majority of our incorporated communities are Tree City USA certified and many private HOA communities have HOA rules that require tree cover maintenance. These are good things for our tree cover and our communities are much more livable, enjoyable, and healthy due to our amazing urban forest. To maintain our urban forest though we need to plan tree planting and management, if for now other reason than to replace trees that die or are lost over time. As our area grows and develops new trees need to be planted in urban areas to replace ones lost as the natural forest was converted. Doing this right means more success, healthier trees, and better use of public funds through better survival. Here is what you need to know to plant a tree right in your urban setting.
Right Tree Right Place! Planning is key and far too many times it is overlooked. Urban forests have limited root and crown growing room. Planting a towering Southern Red Oak in an area with only space for 40% of this tree at maturity will not be a success. Yes, that tree is small and dainty now, but in our climate it will grow into a towering tree in no time. Similarly, trees that drop fruit (like Sweetgum) or create a bit of a mess (like Sycamore) may not fit well in an area. Perform a through assessment of the planting spot and determine what size and characteristics are needed. Then compare it with our outstanding variety of native trees and select the right one.
Thoroughly assess the planting site and determine any mitigations that are needed. Locate and determine all utilities, rights of way, and other issues. Remember that utilities have the right to trim any tree that comes into their right of way and that includes roots and branches. If the tree will interfere consider relocation or selecting a smaller tree. Sometimes a tree will tolerate the maintenance activities associated with a utility or right of way but sometimes it will not.
Determine the soil characteristics on site and perform a soil test. This is probably the most overlooked issue, and many people plant trees without any thought to the soil. Since trees are big and tough their site needs often get ignored. It is easy to forget trees have preferences in water depth, PH, density, and nutrient needs. Compaction is particularly a problem in urban settings and a soil test can detect it. If compaction is a problem, develop a plan to mitigate it prior to planting.
Determine if amendments are needed and/or beneficial and apply accordingly. For urban trees preparing a planting hole and root establishment zone is critical to success. Fortunately we have some of the best options and methods of doing this now that we ever have before. Biochar, soil mycorrhizae (beneficial fungi) inoculants, long term release tailored fertilizers, and multiple other options mean a planting hole can be so much more than a hole. Explore the options and select what time and budgets allow, the tree will certainly do much better with good amendments to establish a strong root system early.
Plant the tree properly and using good techniques. You can take a whole class on this and still have some more to gain on technique. It is a much more complex operation than it initially appears. It is more than just getting the tree in the ground straight and level. It starts from the minute the tree arrives from the grower to the maintenance over the establishment years. Common mistakes are too small/too large a hole, incorrect depth, improper backfill and setting, failure to mulch or improper mulching technique.
Arbor Day is a good reminder that trees are a valuable and important part of the world we inhabit. That is true in a pristine forest or under the favorite shade tree at your local golf course. Except for some of the shortest-lived trees most will certainly outlive us. The longest will outlive tens of generations of we humans. Let’s hope that the trees we plant this Arbor Day are successful in establishment and benefit many generations to come.