Galls or cecidia are a kind of swelling growth on the external tissues of plants. Plant galls are abnormal outgrowths of plant tissues, similar to benign tumors or warts in animals. They can be caused by various parasites, from viruses, fungi and bacteria, to other plants, insects and mites. Plant galls are often highly organized structures so that the cause of the gall can often be determined without the actual agent being identified. This applies particularly to insect and mite plant galls. The study of plant galls is known as cecidology.
A frond is a large, divided leaf. In both common usage and botanical nomenclature, the leaves of ferns are referred to as fronds and some botanists restrict the term to this group. Other botanists allow the term frond to also apply to the large leaves of cycads, as well as palms (Arecaceae) and various other flowering plants, such as mimosa or sumac. "Frond" is commonly used to identify a large, compound leaf, but if the term is used botanically to refer to the leaves of ferns and algae it may be applied to smaller and undivided leaves.
Silphium laciniatum is a species of flowering plant in the family Asteraceae known commonly as compassplant or compass plant. It is native to North America, where it occurs in Ontario in Canada and the eastern and central United States as far west as New Mexico. Other common names include prairie compass plant, pilotweed, polarplant, gum weed, cut-leaf silphium, and turpentine plant. It is a rosinweed of genus Silphium.
Asplenium platyneuron, commonly known as ebony spleenwort or brownstem spleenwort, is a fern native to North America east of the Rocky Mountains. It takes its common name from its dark, reddish-brown, glossy stipe and rachis, which support a once-divided, pinnate leaf. The fertile fronds, which die off in the winter, are darker green and stand upright, while the sterile fronds are evergreen and lie flat on the ground. An auricle at the base of each pinna points towards the tip of the frond. The dimorphic fronds and alternate, rather than opposite, pinnae distinguish it from the similar black-stemmed spleenwort.
Gymnocarpium dryopteris, the western oakfern, common oak fern, oak fern, or northern oak fern, is a deciduous fern of the family Cystopteridaceae. It is widespread across much of North America and Eurasia. It has been found in Canada, the United States, Greenland, China, Japan, Korea, Russia, and most of Europe. It is a seedless, vascular plant that reproduces via spores and have a life cycle with alternating, free-living sporophyte and gametophyte phases.
Dryopteris affinis, the scaly male fern or golden-scaled male fern, is a fern native to western and southern Europe and southwestern Asia. It is most abundant on moist soils in woodlands in areas with high humidity, such as the British Isles and western France. In the Mediterranean region and the Caucasus it is confined to high altitudes.
Dryopteris marginalis, vernacularly known as the marginal shield fern or marginal wood fern, is a perennial species of fern found in damp shady areas throughout eastern North America, from Texas to Minnesota and Newfoundland. It favors moderately acid to circumneutral soils in cooler areas but is fairly drought-resistant once established. In the warmer parts of its range, it is most likely to be found on north-facing non-calcareous rock faces. It is common in many altitudes throughout its range, from high ledges to rocky slopes and stream banks. Marginal wood fern's name derives from the fact that the sori are located on the margins, or edges of the leaflets.
Andricus kollari, also known as the marble gall wasp, is a parthenogenetic species of wasp which causes the formation of marble galls on oak trees. Synonyms for the species include Cynips kollari, Andricus quercusgemmae, A. minor, A. indigenus and A. circulans.
Phegopteris hexagonoptera, commonly called the broad beech fern, is a common forest fern in the eastern United States and adjacent Ontario. It grows from a creeping rootstock, sending up individual fronds that more or less clump. Its native habitat includes moist, undisturbed, hardwood forests.
Andricus foecundatrix is a parthenogenetic gall wasp which lays a single egg within a leaf bud, using its ovipositor, to produce a gall known as an oak artichoke gall, oak hop gall, larch-cone gall or hop strobile The gall develops as a chemically induced distortion of leaf axillary or terminal buds on pedunculate oak or sessile oak trees. The larva lives inside a smaller hard casing inside the artichoke and this is released in autumn. The asexual wasp emerges in spring and lays her eggs in the oak catkins. These develop into small oval galls which produce the sexual generation of wasps. A yew artichoke gall caused by the fly Taxomyia taxi also exists, but is unrelated to the oak-borne species. Previous names or synonyms for the species A. fecundator are A. fecundatrix, A. pilosus, A. foecundatrix, A. gemmarum, A. gemmae, A. gemmaequercus, A. gemmaecinaraeformis and A. quercusgemmae.
Diplolepis rosae is a gall wasp which causes a gall known as the rose bedeguar gall, bedeguar gall wasp, Robin's pincushion, mossy rose gall, or simply moss gall. The gall develops as a chemically induced distortion of an unopened leaf axillary or terminal bud, mostly on field rose or dog rose shrubs. The female wasp lays up to 60 eggs within each leaf bud using her ovipositor. The grubs develop within the gall, and the wasps emerge in spring; the wasp is parthenogenetic with fewer than one percent being males.
Dryopteris goldieana, commonly called Goldie's wood fern, or giant wood fern is a fern native to the eastern United States and adjacent areas of Canada, from New Brunswick to Ontario and Georgia. It is the largest native North American species of Dryopteris and along with ostrich fern it is one of the largest ferns in eastern North America. Specimens are known with fronds six feet tall. D. goldieana hybridizes with many other species of Dryopteris and the hybrids tend to be larger than the pure species. It was named by William Hooker in honor of its discoverer, John Goldie. The epithet was originally published as goldiana, but this is regarded as a misspelling to be corrected.
Dryopteris intermedia, the intermediate wood fern or evergreen wood fern, is a perennial, evergreen wood fern native to eastern North America. It is a diploid species, and is the parent of several species of hybrid origin, including Dryopteris carthusiana. Other common names for this species include intermediate shield fern, fancy wood fern, fancy fern, glandular wood fern, American shield fern and common wood fern.
Fern sports are plants that show marked change from the normal type or parent stock as a result of mutation. The term Morphotype is also used for any of a group of different types of individuals of the same species in a population. Fern fronds in sports are typically altered in several ways, such as the frond apex divided and pinnae similarly duplicated.
Adiantum viridimontanum, commonly known as Green Mountain maidenhair fern, is a fern found only in outcrops of serpentine rock in New England and Eastern Canada. The leaf blade is cut into finger-like segments, themselves once-divided, which are borne on the outer side of a curved, dark, glossy rachis. These finger-like segments are not individual leaves, but parts of a single compound leaf. The "fingers" may be drooping or erect, depending on whether the individual fern grows in shade or sunlight. Spores are borne under false indusia at the edge of the subdivisions of the leaf, a characteristic unique to the genus Adiantum.
Epipompilus insularis is a species of spider wasp which is endemic to New Zealand and it is the only species of the genus Epipompilus found in New Zealand.
Psychoides filicivora is a moth of the family Tineidae first described by Edward Meyrick in 1937. First found in Ireland in 1909, it is possible that the moth was introduced from imported ferns from Asia. The moth can be found from spring though autumn in a series of generations. The species overwinters as a larva.
Profenusa thomsoni, the amber-marked birch leaf miner, is a species of sawfly in the family Tenthredinidae. It is native to the Palearctic realm but has spread to North America. The larvae feed on the foliage of birch trees.
Chirosia grossicauda is a species of fly found in Europe. The larvae mine the lower rachis of bracken causing a swelling, known as a gall.
