How does holly attach to oak tree branch and grow without grafting?

Answer 1

That is mistletoe. Holly is a separate bush or tree.

From Botanical.com:

The well-known Mistletoe is an evergreen parasitic plant, growing on the branches of trees, where it forms pendent bushes, 2 to 5 feet in diameter. It will grow and has been found on almost any deciduous tree, preferring those with soft bark, and being, perhaps, commonest on old Apple trees, though it is frequently found on the Ash, Hawthorn, Lime and other trees. On the Oak, it grows very seldom. It has been found on the Cedar of Lebanon and on the Larch, but very rarely on the Pear tree.
When one of the familiar sticky berries of the Mistletoe comes into contact with the bark of a tree - generally through the agency of birds - after a few days it sends forth a thread-like root, flattened at the extremity like the proboscis of a fly. This finally pierces the bark and roots itself firmly in the growing wood, from which it has the power of selecting and appropriating to its own use, such juices as are fitted for its sustenance: the wood of Mistletoe has been found to contain twice as much potash, and five times as much phosphoric acid as the wood of the foster tree. Mistletoe is a true parasite, for at no period does it derive nourishment from the soil, or from decayed bark, like some of the fungi do - all its nourishment is obtained from its host. The root becomes woody and thick.

---Description---The stem is yellowish and smooth, freely forked, separating when dead into bone-like joints. The leaves are tongue-shaped, broader towards the end, 1 to 3 inches long, very thick and leathery, of a dull yellow-green colour, arranged in pairs, with very short footstalks. The flowers, small and inconspicuous, are arranged in threes, in close short spikes or clusters in the forks of the branches, and are of two varieties, the male and female occurring on different plants. Neither male nor female flowers have a corolla, the parts of the fructification springing from the yellowish calyx. They open in May. The fruit is a globular, smooth, white berry, ripening in December.

Mistletoe is found throughout Europe, and in this country is particularly common in Herefordshire and Worcestershire. In Scotland it is almost unknown.

The genus Viscum has thirty or more species. In South Africa there are several, one with very minute leaves, a feature common to many herbs growing in that excessively dry climate; one in Australia is densely woolly, from a similar cause. Several members of the family are not parasitic at all,being shrubs and trees, showing that the parasitic habit is an acquired one, and now, of course, hereditary.

Mistletoe is always produced by seed and cannot be cultivated in the earth like other plants, hence the ancients considered it to be an excrescence of the tree. By rubbing the berries on the smooth bark of the underside of the branches of trees till they adhere, or inserting them in clefts made for the purpose, it is possible to grow Mistletoe quite successfully, if desired.

Answer 2

Hello,
You mean mistletoe?
This is a virus, fungus. We have it here in Oregon and it is a crop one can get some money for. Easiest to shoot it down with a little 22.
Since it is a fungus it spreads like one too.

Answer 3

Mistletoe is correct and it is a parasite, living off of others.

Answer 4

that's mistletoe