appears to be under the control of the invader. The haustorium may be mycelium or root-shaped. In plants Mistletoes (including Loranthaceae and Viscaceae) attach to their hosts via a haustorium. The haustoria attacks the host's xylem and/or phloem and attaches itself to the host. This structure both anchors the mistletoe, and taps into the host plant. Mistletoes use passive mechanisms to draw water from their hosts. They keep their leaf stomata open night and day which sets up a moisture gradient between mistletoe and host. A second meaning of 'haustorium' in botany is to describe tissues in a developing plant embryo that transfer nutrients from the seed's endosperm to the embryo. These tissues are found widely in the seeds of flowering plants. References Bibliography ANBG: What is mistletoe Accessed 22 January 2018. ANBG: Haustoria Accessed 22 January 2018. Fungal plant pathogens and diseases Plant morphology