Julien Joseph Vesque (8 April 1848, in Luxembourg – 25 July 1895, in Paris), was a French naturalist, noted for his work on the agricultural and horticultural benefits deriving from the study of plant physiology.
He was the father of Marthe and Juliette, the celebrated circus aficionados known as the Vesque Sisters.
His main area of study was water transportation in plants.
In 1880 he stated that the movement of water in plants is due to both transpiration and root pressure.
He was also interested in the effect of temperature on root absorption of water from the soil.
Vesque proved that water moved through the cavities of the vessels and not along the walls of plant vessels.
During his research he invented laboratory instruments for studying transpiration in plants.
He is denoted by the author abbreviation Vesque when citing a botanical name.