| Catalpa ovata | |
|---|---|
| |
| Flowers | |
Scientific classification 
| |
| Kingdom: | Plantae |
| Clade: | Tracheophytes |
| Clade: | Angiosperms |
| Clade: | Eudicots |
| Clade: | Asterids |
| Order: | Lamiales |
| Family: | Bignoniaceae |
| Genus: | Catalpa |
| Species: | C. ovata
|
| Binomial name | |
| Catalpa ovata | |
| Synonyms[2][3][4] | |
Catalpa ovata, the yellow catalpa[1][5] or Chinese catalpa[1] (Chinese: 梓; pinyin: zǐ), is a pod-bearing tree native to China. Compared to C. speciosa, it is much smaller, typically reaching heights between 20 and 30 feet (6 and 9 m). The inflorescences form 4–10-inch-long (100–250 mm) bunches of creamy white flowers with distinctly yellow tinging; individual flowers are about 1 inch (25 mm) wide. They bloom in July and August.[5] The leaves are very similar in shape to those of Paulownia tomentosa, having three lobes (two are abruptly truncated on either edge, with a third, central, slightly acute, pointed lobe forming the leaf apex), and are darkly green.[5][6] Fruits are very narrow, foot-long pods.[5]
Although native to the more temperate provinces within China (Anhui, Gansu, Hebei, Heilongjiang, Henan, Hubei, Jiangsu, Jilin, Liaoning, Nei Monggol, Ningxia, Qinghai, Shaanxi, Shandong, Shanxi, Sichuan, Xinjiang),[1] C. ovata is also cultivated in North America and Europe, and has become a parent of Catalpa × erubescens with the American species Catalpa bignonioides.[1][5] It is commonly used to make the undersides of qin.[7]
The plant contains dehydro-alpha-lapachone[8] (DAL) which inhibits vessel regeneration, interferes with vessel anastomosis, and limits plexus formation in zebrafish.[9] DAL also controlled the development of the fungi rice blast, tomato late blight, wheat leaf rust, barley powdery mildew and red pepper anthracnose (Colletotrichum coccodes (Wallr) S Hughes). The chemical was particularly effective in suppressing anthracnose.[10]
