Upright spikes of lilac trumpets in late April, out before the leaves. Visible from a long way off, which makes spring the time to map it.Photo: iNaturalist (CC0), Lori B

Upright spikes of lilac trumpets in late April, out before the leaves. Visible from a long way off, which makes spring the time to map it.Photo: iNaturalist (CC0), Lori B

Clusters of woody pecan-sized capsules that dry brown and split in two. They sit on the bare tree all winter, so it is identifiable at a hundred yards in February.Photo: iNaturalist (CC0), Ira Gershenhorn

Where you meet it: rooted in a crack at the foot of a wall, on a road cut, a rail bank or anywhere else nothing else will grow.Photo: iNaturalist (CC0), Bethany Teigen

Where you meet it: rooted in a crack at the foot of a wall, on a road cut, a rail bank or anywhere else nothing else will grow.Photo: iNaturalist (CC0), Bethany Teigen

🔴 Invasive - Remove

Princess Tree

Paulownia tomentosa

This is an invasive species that harms native ecosystems. It should be removed when found to protect local plant and wildlife habitats.

Description

A fast-growing tree with enormous heart-shaped, velvety leaves, showy purple trumpet flowers before the leaves in April, and woody seed capsules that hang on all winter. Each capsule holds thousands of tiny winged seeds.

Where you'll find it

Steep road cuts, rail banks, rocky slopes and stone walls. It roots in places nothing else will.
Disturbed ground in full sun, and along stream corridors after a flood.

Background

Native to: China

Seeds were used as packing material for porcelain shipped from China in the 1800s and spilled along rail lines and ports; it was also planted as an ornamental and, later, as a plantation timber tree.

Ecological impact

Colonises rock outcrops, stream edges, road cuts and burned ground faster than natives can, then shades them out under leaves the size of dinner plates. One tree sheds up to twenty million seeds a year.

How to identify

The leaf

Enormous heart-shaped leaves in facing pairs.

Colour and texture: Mid-green and velvety, sometimes a foot across on young growth. Opposite pairs, with a hollow or chambered pith in the twig.

Leaves: opposite, heart-shaped, 6–16 inches across, fuzzy on both sides, on stout hairy stalks. Sprouts from cut stumps carry even bigger leaves.

Flowers: upright clusters of purple, fragrant, trumpet-shaped flowers in April, before the leaves.

Capsules: oval, woody, 1–2 inches, green then brown, splitting in autumn and persisting all winter — around two thousand winged seeds in each. Fuzzy flower buds are visible on the twigs all winter too.

Twigs: stout, with a chambered pith.

Seedheads & fruit

Capsules September through the winter.

Clusters of woody, pecan-sized capsules that dry brown and split in two; the old capsules and fat fuzzy flower buds sit on the bare tree all winter.

Why it matters: One tree can release millions of tiny winged seeds, and those winter capsules make it identifiable at a hundred yards in February.

Preferred removal method

Wrench the crown out

A woody crown too big to pull and too stubborn to cut: wineberry, multiflora rose, barberry, bush honeysuckle, tree seedlings.

1Cut the top growth back first so you can reach the base, then clamp the weed wrench jaws as low as you can, at soil level.
2Lever the handle back in one long, steady arc. Let the tool do it, not your back.
3The root ball should lift with the stem. Shake the soil off, and leave the hole; stamping it closed buries any seed you just exposed.

Avoid: Do not clamp halfway up the stem. It snaps, and the crown stays in the ground and re-sprouts.

Grab from the kit, in this order

Disposal

Bag it. Bag every capsule within reach. Each one holds thousands of seeds and they are splitting now.

Lookalikes

Northern catalpa, our native, also has huge heart-shaped leaves, but they are usually in whorls of three rather than opposite pairs, its flowers are white and come in June, and its fruit is a long bean pod, not a round capsule.