Catalpa Species, Propagation, Benefits, Diseases, and Care

Catalpa tree belongs to the family Bignoniaceous (700 species of flowering plants). These woody flower-bearing plants are mostly found in the regions of Asian countries, especially in East Asia. Subtropical areas and temperate regions are the most suitable places for their growth and propagation.

The origin of the name Catalpa is the Greek word Kutuhlpa which translates as a tree with wings or winged head tree. The other common name for this woody plant is Catawba. Catalpa trees are deciduous. Another famous specification and key identification is its flowering pattern.

The shape of its leaves is typical heart-shaped. The pattern is branched for flowering (zigzag branched) known as panicles. The flowers are white and yellow in color and the tree shows blossom in 3 years while it bears fruits after five to six years. The fruits are of the fused type named siliques when it is ripened.

These long and thin fruits when dried are termed silicle. The length of the tree is almost 50 to 60 feet (15 to 18 meters). When in full bloom, its foliage is thick and heavy. Which is perfect for shading in sun and rain as well. A hybrid of Catalpa is now being used as an ornamental plant. That breed is formed by the cross of Erubescens and Catalpa^[1]Liu, Y., et al., Anatomical features and its radial variations among different catalpa Bungei clones. Forests, 2020. 11(8): p. 824. Read^[2]Keykhasabera, M., Verticillium wilt of woody plants with emphasis on olive and shade trees. Unraveling aspects of spatial and temporal distribution of Verticillium dahliae in olive, maple and ash … Continue reading.

Catalpa Species

Catalpa has more than 12 species spread around the globe. Some of the most common are discussed below:

1. Southern Catalpa (Catalpa bignonioides)

Specifically native to China, Alabama, Georgia, and Florida. This is also called the bean tree. Each node has three to 4 leaves at its branch. Sometimes flowers have sweet and light fragrances and are usually yellow. Leaves are broad and large. Thin and long but slender fruits are seen in the fruiting season.

2. Northern Catalpa (Catalpa speciosa)

Common names for this species are the Cigar tree, Bois tree, and Hardy Western Catalpa. The arrangement of leaves is opposite and has an almost zigzag pattern. Lines and spots of purple shade on yellow flowers appear appealing. These are also used for shading and ornamental purposes. This is also the source of heartwood and cedarwood. Its wood is also used in design carving and artistic work.

3. Chinese Catalpa (Catalpa ovata)

It has a tuft of creamy white flowers, with a height of 25 to 35 feet, and lobed leaves. It is used in the making of musical instruments. Fruits are thin and long. It is commonly found in Europe and America as well. Wood is resistant to degradation^[3]Acebes-Doria, A.L., T.C. Leskey, and J.C. Bergh, Host plant effects on Halyomorpha halys (Hemiptera: Pentatomidae) nymphal development and survivorship. Environmental Entomology, 2016. 45(3): p. … Continue reading.

4. Dwarf Catalpa (Catalpa bungei)

This is an Indian native species called a dwarf bean catalpa tree. It is thought that this tree has an origin in Belgium. It has its uses in the horticulture department and landscapes. Dwarf Catalpa has white bloom in late summer.

These also have characteristic heart-shaped broad leaves. Another interesting feature of this species is the nests of pigeons. The best suitable height to grow Catalpa bungei is 10 to 12 feet^[4]Shi, H., et al., Physiological and transcriptional responses of Catalpa bungei to drought stress under sufficient and deficient-nitrogen conditions. Tree physiology, 2017. 37(11): p. 1457-1468. Read.

5. Catalpa of Cuba (Catalpa brevipes)

This is the smallest tree among its other family members in Bignoniaceae. It loves to grow on mountains or in hilly places. As per name indicates it is specifically native to Cuba, Dominica, and Syria. It does not grow well in cold climate regions rather it grows rapidly in hot and dry conditions^[5]Mortimer, C., VI. An account of Mr. Mark Catesby’s essay towards the natural history of Carolina and the Bahama Isands, with some extracts out of the first three sets. Philosophical Transactions of … Continue reading.

Propagation of Catalpa species

Whichever soil one has chosen for the plantation of Catalpa tree must be ready before the plantation procedure. Soil should be moist and wet.

1. Sapling Plantation

The young saplings are chosen with care having a thick and strong main stem. To plant this tree, a hole must be dug and it should be filled with sandy and well-drained soil is added into that hole. Carefully place the young sapling into it; water it properly. The use of fertilizers is mainly recommended for this kind of young plantlets.

2. Propagation by Cutting

Propagation by cutting is recommended if one is planning to plant Catalpa plant in hot weather (summer season). In this protocol, we must choose the stem for cutting that is free of any fungal infection or insect pest. Cut the branched stem 6 to 7 inches long and remove the leaves from the lower half of the cutting.

Cut the stem from the bottom along its length. Make sure that the cutting of the stem is divided into two legs like cuttings. Take good quality rooting hormone and media top dip the lower bottom of the cutting for a while before potting into a pot.

A mud pot is taken and filled with an equal mixture of peat, sand, coarse sand, and perlite. Mix them well. Put a finger into the potting soil and put the dipped stem cutting into the pot. Place it in a partially exposed area to sunlight; water it less when it is a small plantlet.

Check for root system development and then shift it into the soil as discussed above. Two to three healthy leaves have to be there on the stem cutting which is an indication of a healthy plant^[6]Sokolov, R., Comparative study on the growth and development of annual and biannual plants of species from genus Catalpa at the conditions of Sofia field. Rasteniev’dni Nauki/Bulgarian Journal … Continue reading.

Uses and benefits of Catalpa trees

There are several industrial and medicinal uses for this woody plant some of these uses are listed below:

Medicinal usage

• Its leaves are used in some kind of medicinal tea.
• The other use of its extract is against snake bites. It acts as an antidote against snake venom.
• One of its extracts acts as a laxative, helping with constipation.
• Some of the old medicines were prepared from this plant that was used to cure whooping cough.
• Ointments and lotions are prepared for skin allergies and against soreness or inflammation.
• Its leaves are also used as pain relief agents, especially over wounds and cuts.

Furniture work and firewood

• It has hardwood which is used in furniture industries at the commercial level.
• In winter, its dry wood is a nearly perfect source of firewood and fuel.
• Its wood is suitable for making cabinets and fences.
• Its foliage is quite thick perfect for shading.
• These trees can also be used as windbreakers around the fragile crops to keep them standing in strong stormy winds.
• Catalpa wood is not easily degraded thus for the preferred wood type being used in households^[7]Yang, H., et al., Catalpa ovata G. Don. potential medicinal value of leaves. Thermal Science, 2020. 24(3 Part A): p. 1713-1720. Read.

Diseases of Catalpa trees

Verticillium Wilt is a fungal pathological condition that spreads through the soil as the etiological agent resides in the soil and attaches to the susceptible plants. This can severely damage the whole Catalpa tree. This fungal infection is acquired through the soil, transferred to roots, and further spread to other parts by vascular bundles.

This purple or brownish-blue fungal infection causes wilting of branches eventually the whole tree can die of it. The sapwood got decolorized. This can be avoided by the use of nitrogenous fertilizers in large quantities^[8]Chen, W., et al., Effects of arbuscular mycorrhizal fungi on growth and physiological performance of Catalpa bungei CA Mey. under drought stress. Forests, 2020. 11(10): p. 1117. Read.

Another important fungal issue is Powdery Mildew. It is creamy and whitish fungus appearing over leaves and young branches. It can be cured by spraying effective fungicides. Young leaves are damaged because of their attack. Symptoms are deformed, damaged, and folded or curled leaves^[9]Chinan, V.C. and C.C. Mânzu, Distribution, Incidence and Severity of the Catalpa Powdery Mildew Caused by Erysiphe elevata in North-Eastern Romania. Notulae Scientia Biologicae, 2018. 10(4): p. … Continue reading.

The third important fungal disease is Leaf Spots. The causative agent for Leaf Spots is the Phyllosticta species. In this pathological condition, small and large brownish spots are seen on Catalpa leaves. This fungal species attacks in damped and cool weather when the humidity level is higher as compared to dry weather. Root rot of the Catalpa tree is caused by a fungus Phymatotrichum omnivorum^[10]Olson, J., Anthracnose and Other Common Leaf Diseases of Deciduous Shade Trees. 2015. Read.

Insect pests are also important agents damaging this deciduous plant. Different species of Moths are major pests of Catalpa. The important species is the sphinx commonly called Catalpa Worm. It feeds on the leaves of the foliage of the tree. Caterpillars have devastating effects on leaves^[11]Bray, J.L., Responses of the Catalpa Sphinx, Ceratomia Catalpae, and Its Primary Parasitoid, Cotesia Congregata, to Varying Levels of Iridoid Glycosides in Catalpa. 2015. Read.

Care of Catalpa Tree

• Loamy and clay soil are preferable for the growth of Catalpa tree; although it has been observed that Catalpa tree can grow in any type of soil so; generally there is no need for soil specifications.
• Pruning must be done to ensure healthy foliage. This will help in removing damaged leaves from fungal attacks.
• Pruning is also done to maintain a single main stem. Multiple trunks decrease the strength of the tree and become more prone to insect attack.
• Fertilize it often when the tree is young; once it gets mature or fully grown to its height there is no need to use fertilizers for it^[12]Voth, L., G. Cesarini, and N. Perry, Featured Tree. 2018. Read.