The Tackiness in Tacky

Katharine Washburn and John S. Major include in their edition of World Poetry: An Anthology of Verse From Antiquity to Our Time excerpts from The Mercian Hymns by Geoffrey Hill where one finds the intriguing line

Candles of gnarled resin, apple-branches, the tacky mistletoe.
I would not long ago have taken the "tacky" mistletoe to be signalling bad taste in plants. However, having been instructed by the little 10 minute film "Spreading Seeds" in the compilation Plant World: The Biology of Flowering and Non-flowering Plants released by Films for the Humanities and Sciences, I have a particular appreciation for the tackiness of mistletoe. It so happens that the film shows a long string of seed emanating from a bird's bum.

The film shows what the entry on the Royal Horticultural Society puts in more general terms: "The berries are often spread by birds from one tree to another, and this is how the large rounded clumps of mistletoe form in tree branches." It turns out that the RHS is not being coy but accurate in describing the means of propagation at a level of generality suitable to cover the varied means birds spread the seed. See, for example, the Wikipedia entry on mistletoe which is expansive on the origin of the tackiness:
Depending on the species of mistletoe and the species of bird, the seeds are regurgitated from the crop, excreted in their droppings, or stuck to the bill, from which the bird wipes it onto a suitable branch. The seeds are coated with a sticky material called viscin. Some viscin remains on the seed and when it touches a stem, it sticks tenaciously. The viscin soon hardens and attaches the seed firmly to its future host, where it germinates and its haustorium penetrates the sound bark.
The RHS provides advice on how to grow your own mistletoe should you have a mature tree in need of tacky decoration.

And so for day 1404