Trees of all ages can become infected. Symptoms are first seen at the base of the crown on older needles. Infected needles typically develop yellow and tan spots and bands, which soon turn red. Then, as the disease progresses, the ends of the needles turn reddish-brown while the needle base remains green. It is within the red bands that the small, black, spore-containing fruit bodies tend to be found, with symptoms being most apparent in June and July. Spores are released from the fruit bodies during this period, leading to infection of the current year’s needles. After this point, the symptomatic needles are shed, and branches can acquire a ‘lion’s tail’ appearance typical of the disease, with only a tuft of the recently infected current year’s needles remaining at the branch ends. This defoliation can continue year on year and gradually weaken the tree, significantly reducing timber yields and causing the death of the tree.