Hypoxylon (hi-póx-i-lon) cankers are prevalent and highly visible diseases affecting oaks and other hardwoods in Florida. These cankers are caused by one or more Hypoxylon fungi. Trees infected with Hypoxylon often show evidence of severe injuries on the branches or stem and/or advanced dieback or decline. The bark of infected trees typically sloughs off, often near injuries or along the trunk and major branches, revealing one of two types of fungal signs.

In the spring or early summer, conspicuous, powdery, greenish-to-brown masses of spores called conidia are produced on the surface of crusty sheets of fungus tissue called stromata.

Later in the summer or fall, after the powdery conidia are gone, the fungal stromata thicken, become very firm, appearing silver-gray, brownish to black in color. On close inspection, minute (less than 1/32″), black, slightly raised dots are visible on the surface of the stroma. These dots are the tips of small cavities, producing spores which are discharged to the air looking for the next stressed oak.

Stromata vary from a few inches to several feet in length up and down the trunks of infected trees and are the most readily recognizable indicator of Hypoxylon infections.Hypoxylon infections originate when spores come into contact with injured or stressed tissues of susceptible trees during the late summer, fall or winter. Spores are spread by wind, splashing rain and, presumably, by certain insects, birds and rodents. The fungus develops in the bark and wood tissues.
If any of your trees are showing signs of hypoxylon canker, chances are, it’s time to remove the tree so as to prevent the spread to surrounding trees and to prevent the infected tree from becoming more of a hazard.

Pinellas County is home to many varieties of beautiful pine trees. The most common are the Slash Pine and the Sand Pine. While these trees add value and beauty to the Pinellas landscape, they are very susceptible to beetle infestation. Namely, the Ips Engraver Beetle. Trees attacked by Ips bark beetles, whether in the forest or around the home, are usually noticed when needles turn yellow or red. Upon closer examination, infested trees will have dry, reddish-brown boring dust in the bark crevices. Some trees may have dime-size or smaller, white to reddish-brown projections, called pitch tubes in the bark crevices

Ips beetles usually attack weakened, dying, or recently felled trees and fresh logging debris. Large numbers Ips may build up when natural events such as lightning storms, ice storms, tornadoes, wildfires, and droughts create large amounts of pine suitable for the breeding of these beetles. Ips populations may also build up following forestry activities, such as prescribed burns that get too hot and kill or weaken pines and clear-cutting or thinning operations that compact soils, wound trees, and leave large amounts of branches, cull logs, and stumps for breeding sites.Adult Ips beetles carry numerous spores of a bluestain fungus, Ceratocystis ips (Rumbold) C. Moreau, in their gut. When the adults attack trees or logging slash, the bluestain spores are excreted with beetle feces into egg galleries, where the spores germinate. Bluestain fungus colonies grow into the outer sapwood of infested pines, stopping the upward flow of water to the tree crown. Lack of water causes needles to wilt and die, gradually changing their color, from dull green to yellow green to red brown. These color changes may occur in 2 to 4 weeks during the summer, but take several months in the winter.

B&T’s Tree Service in Clearwater recommends complete tree removal when trees are infested with Ips Engraver Beetles.

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Ips Beetle Entry Wound

The Live Oak tree is one of the most abundant types of trees in Clearwater Florida. Sprawling limbs, and a huge canopy is what we tend to recognize most about the Live Oak tree.

Although live oaks retain their leaves nearly year-round, they are not true evergreens. Live oaks drop their leaves immediately before new leaves emerge in the spring. Occasionally,senescing leaves may turn yellow or contain brown spots in the winter, leading many to mistakenly believe the tree has oak wilt, whose symptoms typically occur in the summer.^[6] A live oak’s defoliation may occur sooner in marginal climates or in dry or cold winters.^[7]

The bark is dark, thick, and furrowed longitudinally. The leaves are stiff and leathery, with the tops shiny dark green and the bottoms pale gray and very tightly tomentose, simple and typically flattish with bony-opaque margins, with a length of .75 – 6 inches (2 – 15 cm) and a width of .4 – 2 inches (1 – 5 cm), borne alternately. The male flowers are green hangingcatkins with lengths of 3 – 4 inches (7.5 –10 cm). The acorns are small, .4 – 1 inch (1 – 2.5 cm), oblong in shape (ovoid or oblong-ellipsoid), shiny and tan-brown to nearly black, often black at the tips, and borne singly or in clusters.^[5][7]

Depending on the growing conditions, live oaks vary from a shrub-size to large and spreading tree-size: typical open-grown trees reach 20 meters (60 feet) in height, with a limb spread of nearly 27 meters (80 feet).^[8] Their lower limbs often sweep down towards the ground before curving up again. They can grow at severe angles, and Native Americans used to bend saplings over so that they would grow at extreme angles, to serve as trail markers.

The branches frequently support other plant species such as rounded clumps of ball moss, thick drapings of Spanish moss, resurrection fern, and parasitic mistletoe.

The southern live oak has a deep tap-root that anchors it when young and eventually develops into an extensive and widespread root system. This, along with its low center of gravity and other factors, makes the southern live oak extremely resistant to strong sustained winds, such as those seen in hurricanes.^[9]

The southern live oak grows in a wide variety of sites but has low fire-resistance and occurs most any place free from fire that is not too wet.^[7][10] They tend to survive fire, because often a fire will not reach their crowns. Even if a tree is burned, its crowns and roots usually survive the fire and sprout vigorously. Furthermore, live oak forests discourage entry of fire from adjacent communities because they provide dense cover that discourages the growth of a flammable understory.^{[citation needed]} They can withstand occasional floods and hurricanes, and are resistant to salt spray and moderate soil salinity. Although they grow best in well-drained sandy soils and loams, they will also grow in clay.^[11] Live oaks are also surprisingly hardy. Those of southern provenance can easily be grown in USDA zone 7 and the Texas live oak (Quercus virginiana var. fusiformis), having the same evergreen foliage as the southern variety, can be grown with success in areas as cold as zone 6. Even with significant winter leaf burn, these trees can make a strong comeback during the growing season in more northerly areas, such New Jersey, southern Ohio, and southern Connecticut.

Crape myrtles tend to grow numerous suckers from its base, and therefore do require some pruning every year — but only minimal pruning. Early training will help eliminate any extensive pruning later on. Extensive pruning or cutting back of crape myrtles each year only causes them to vigorously grow back what was removed. The only tree pruning that should be done each year is to remove suckers and to maintain its attractive shape by removing deadwood and seedpods. And heavy pruning in the winter will not help or force crape myrtles to bloom more.

Crape myrtle varieties come in all shapes, colors and sizes. Pruning large ones into small ones doesn’t make sense. If you want a small, manageable crape myrtle that looks like a shrub, buy a smaller variety. Whacking off and scarring up large crape myrtles each year serves no purpose.