![]() The black colored, circular lesions extruding clear spore masses of Septorioides strobi. Chemical management for this organism differs from other needle disease organisms so check with your local County Extension office for recommendations. Most often, needle tips were straw‐colored to brown while the base of the needle remained green and healthy. In many cases, troubled trees exist directly adjacent to healthy trees in the landscape. Septorioides strobi, recently described as a new species, uncharacteristically affects current season's needles. Hence, the stress of late spring frosts, drought, and wet spring weather favor needle disease outbreaks. Tree crowns begin to look sparse a year after initial infection. Trees commonly shed entirely infected needles, with substantial needle drop occurring in June or with rain. This means an initial infection of current-year needles happens in spring/early summer and the needles show symptoms the following year. However, as is the case with many conifer needle pathogens, that effect has a one-year delay. (2017) determined that an increase in precipitation during May to July - the time when white pine needles are elongating - positively correlates with damage from needle blight pathogens. The bases of needles can remain green, and not all needles in a bundle may get infected. The extent of damage for affected needles varies. Lesions or banding in older needles that develop into brown and yellow expanding areas can cause death to the distal part of the needle. Needle blight pathogens associated with WPND include the fungi Lecanosticta acicula, Lophophacidium dooksii (brown spot needle blight), Bifusella linearis, and Septorioides strobi. ![]() Hot sunny days with air pollution danger warnings can have the gas ozone damaging the needle tips. Photo credit: Rosie Lerner, Purdue University White pine decline symptoms include shriveling bark, oozing resin, or brown needles. Looking at the needles themselves, you may notice brown tips or entire needle discoloration of a disease complex known as White Pine Needle Disease or WPND. Distinguish this from the normal yellow coloration and drop of the oldest needles in the fall. White Pine Needle Diseaseīrowning needles and sparse tufts of new growth often signal the first obvious symptoms of an ailing white pine. Unless a needle cast disease as described below occurs, retain the fallen needles as a natural moisture and pH buffering mulch, or provide up to 3" of mulch up to the drip line for young, planted trees. ![]() White pine tolerate neither root disturbance, street-side planting requiring heavy winter salt maintenance, nor moisture extremes. Above ground canopy space would accommodate a 50 - 100-foot future height with 20 to 40-foot of spread and plenty of sun. Avoid those factors by siting your tree to succeed from the start! Proper soils for best growth includes sandy or loamy noncompacted soils (not clay), a pH between 5.5 and 6.5, and good drainage. Environmental factors leading to white pine decline include soil and moisture conditions white pine is not adapted to growing in. The result is a decline in the overall health of the tree. White pine decline refers to a complex of environmental and biotic factors negatively influencing both short- and long-term health of the plant. Due to its susceptibility to drought, air pollution, and salt, sometimes white pine requires special siting and care in an urban environment. Stroking its leaves can activate an immune response of T-cells in the human body. One mature white pine can intercept up to 4000 gallons of rainwater per year. White pine provides both important ecosystem benefits and enhances health. ![]() A popular landscape tree used for screening (although it naturally loses its bottom branches over time) and its delicate five needled bundle of fine-textured leaves. Widely distributed (10.6% of area), and the tallest of the eastern conifers, some consider white pine the Sequoia of the East. The Pine Tree Riot of 1772, where local townspeople chased and beat the King’s mast surveyors with pine switches may have even inspired the Boston Tea Party. Surveyors for the "King's Woods" blazed the largest white pines with the "King's Broad Arrow", a series of three hatchet slices. Once demanded by the King's Royal Navy for its straight tall masts, Pinus strobus inspired the White Pine Acts of 16 and fueled colonial resistance. Eastern white pine's current status belies its political past and potential future. ![]()
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