black knot

American  

noun

Plant Pathology.

1. a disease of plants, especially of plums and cherries, characterized by black knotlike overgrowths on the branches, twigs, etc., caused by a fungus, Dibotryon morbosa.

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black knot British  

noun

1. a fungal disease of plums and cherries caused by Dibotryon morbosum , characterized by rough black knotlike swellings on the twigs and branches

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Etymology

Origin of black knot

An Americanism dating back to 1835–45

Example Sentences

He would remember how rigorously her hair had been woven into a black knot against the nape of her neck.

From "Snow Falling on Cedars: A Novel" by David Guterson

Her hair had been woven then, as now, into a black knot against the nape of her neck.

From "Snow Falling on Cedars: A Novel" by David Guterson

Japan has furnished to the Middle West and South a hardy, prolific species, P. triflora, generally immune to the black knot, a fungous disease which attacks native plums.

From Trees Worth Knowing by Rogers, Julia Ellen

It is probably what is termed black knot, only the galls have not turned black yet.

From Trees, Fruits and Flowers of Minnesota, 1916 Embracing the Transactions of the Minnesota State Horticultural Society,Volume 44, from December 1, 1915, to December 1, 1916, Including the Twelve Numbers of "The Minnesota Horticulturist" for 1916 by Latham, A. W.

The last group of the Ascomycetes are the “black fungi,” Pyrenomycetes, represented by the black knot of cherry and plum trees, shown in Figure 46.

From Elements of Structural and Systematic Botany For High Schools and Elementary College Courses by Campbell, Douglas Houghton