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Oak leaf with galls of Gall wasp, close-up.
Oak branch with acorns and oak leaves isolated on white.
Oak galls on an oak leaf close-up
An oak is a tree or shrub in the genus Quercus. Oaks have spirally arranged leaves, with lobate margins in many species; some have serrated leaves or entire leaves with smooth margins. The fruit is a nut called an acorn or oak nut borne in a cup-like structure known as a cupule; each acorn contains one seed (rarely two or three) and takes 6–18 months to mature, depending on their species.
Oak galls, ink nuts on oak. Cynips quercusfolii
These galls are produced by tiny Cynipid wasps, which go through a complicated life cycle involving two stages of development. In June, a generation of male and female wasps hatch from currant galls. The adults mate and the female lays fertilized eggs on the undersides of oak leaves. These cause the creation of the spangle galls, in which the grub matures. The spangle galls fall from the leaves in September and the wasp continues to grow within the leaf litter, producing a female-only generation in the following spring.
The Valley Oak, can sometimes be riddled with large growths along the stem. Small wasps produce these oak apples or galls. The large oak apples, are induced by the gallwasp Andricus californicus. Shollenberger Park; Petaluma Wetlands; Petaluma; Sonoma County; California. Quercus lobata.
Oak leaf with galls caused by Neuroterus quercusbaccarum insect (family Cynipidae), isolated on white background, copy space
A oak tree acorn
Horizontal closeup photo of a group of three ripe brown acorns hanging by the stem on an Oak tree with green leaves in late Summer. New England high country NSW.
Bur Oak Acorn Cluster (Quercus macrocarpa) just starting to ripen. They were photographed in the â??sweet lightâ?? of the late afternoon sun.
A tiny acorn growing on an oak tree in a forest.
Macro photo of tree pests eggs on oak leaves isolated on white background. Chemically induced leaf blister galls of a gall wasp Neuroterus numismalis
Small Acorns of Holm Oak (Quercus Ilex)
Macro of galls, gall wasp, infestation of oak leaves in autumn, isolated on white background, Cynipidae, Neuroterus numismalis
Quercus durata, the California scrub oak, or leather oak, is an oak endemic to California. Acorn. Fagaceae.
Oak gall
Acorns and oak leaves in Colorado, USA, North America
Sick Oak leaf when oak bile wasps add eggs to their offspring, white background isolated
Autumn leaf colors against a black background
Austrian oak acorn isolated on white background
Acorns and oak leaves on white background with clipping path included.
Close-up of large Galls on Common oak leaves created by gall wasp Cynips quercusfolii in Estonian boreal forest
Growing brown acorns on an oak branch. Seeds, fruits, nuts of a forest tree. Autumn. Oak acorn
Branch of an oak tree with dry green leaves in autumn
Sessile Oak (Quercus petraea) - Küre Mountains National Park
Gall wasps are insects that lay their eggs in plant tissue. This is where growths, known as Gqallen, develop. The larvae of the gall wasps grow in these growths. Most species of gall wasps occur in the Mediterranean region and on the Black Sea, there are no gall wasps in the tropics.
Oak leaves in autumn on white background
Oak gall
View of an acorn plant.
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