Millbrook

Millbrook

Fast-growing willow shrub named ‘Millbrook’

PUBLIC DOMAIN

Patent expired October 6, 2025. This plant is in the public domain — anyone may propagate and sell it.

No term adjustment or disclaimer is recorded against this patent, so this is the full statutory term — twenty years from the filing date.

Figure 1 of US plant patent PP17646, the photograph of Millbrook printed in the patent.

Figure 1 from US Plant Patent PP17646, reproduced as printed. Photographs in a plant patent are taken by the applicant. Reproduction of the patent document is permitted; the image is shown whole and uncropped for that reason.

Abstract

A distinct female cultivar of Salix purpurea×Salix miyabeana named ‘Millbrook’, characterized by rapid stem growth producing 9% more woody biomass than one of its parents (‘SX64’) and 2% more biomass than a current production cultivar (‘SV1’). ‘Millbrook’ produced greater than 2-fold more stem biomass than two other current production cultivars, ‘SX67’ and ‘SX61’. ‘Millbrook’ can be planted from dormant stem cuttings, produces multiple stems after coppice, and the stem biomass can be harvested when the plant is dormant. In the spring following harvest, the plant will re-sprout very vigorously, producing new stems that can be harvested after two to four years of growth. This harvest cycle can be repeated several times. The stem biomass can be chipped and burned as a source of renewable energy, generating heat and/or electricity. ‘Millbrook’ displays a low incidence of rust disease.

Show the legal claimThe single numbered claim as granted — the legal text that defines what this patent covers.

1. A new and distinct variety of Salix purpurea×Salix miyabeana plant, substantially as illustrated and described herein.

Read the full patent: US Plant Patent PP17646 in full — the complete specification, every figure, and the file history.

The record

Abstract