Mistletoe, Ball moss, Spanish moss, and Lichens in Trees

Mark C. Black, Extension Plant Pathologist, Texas AgriLife Extension Service, Uvalde

Biological interactions• Neutralism - fitness of one species has no effect

on fitness of other (unlikely!)• Commensalism – epiphyte benefited, tree neither

benefited or harmed• Mutualism (symbiosis)- species derive a mutual

benefit• Parasitism - one organism takes from the host for

a long time• Hemiparasitism - takes water and nutrients from

the host, but is photosynthetic and makes some products

• Competition – one species limits space, sunlight

Mistletoe

• Class Magnoliopsida

• Family Viscaceae, 2 genera in Texas

• Diversity Trans Pecos > Edwards Plateau > rest of Texas

• Arceuthobium (dwarf-mistletoe) Phoradendron (mistletoe)

• Phoradendron tomentosum, injerto, Christmas mistletoe

Mistletoe relatives• Commandra

umbellata, bastard toadflax

• Euonymus americanus, brook euonymus

Control?

Plant Epiphytes• Autotrophic• Derive only physical support, not

nutrition from the host• May damage the host• Attach to their host high in the

canopy• Large epiphytes occur most

abundantly in moist tropical forests, but mosses and lichens occur widespread as epiphytes with trees.

Costa Rica

Ball Moss

• Class Liliopsida• Family Bromeliaceae, 2 genera in Texas• Diversity S, E Texas > N Texas• Hechtia (false agave)

Tillandsia (ballmoss,spanish moss)

• Tillandsia baileyi, Bailey ballmossTillandsia recurvata, small ballmoss

Close relatives

• Tillandsia baileyi

Gulf Prairies and MarshesSouth Texas Plains

Control?

• Tillandsia recurvata

Ball moss

Water from condensation on extensive foliar trichomes.Trace minerals from dust.

Part of their nitrogen from decomposition of insects.

Pseudomonas stutzeri, nitrogen-fixing bacterium isolated from interior of T. recurvata.

Ball moss control

• Hand removal

• Chemicals – Kocide 3000sodium bicarbonate (baking soda)potassium bicarbonate (Kaligreen, Arysta; MilStop, BioWorks)

Spanish Moss• Class Liliopsida

• Family Bromeliaceae

• Tillandsia usneoides, spanish moss, blackmoss, pastle

Light fragrance at night

Leaves covered with cup-like, permeable scales that 'catch' moisture and nutrients from the air. In extreme dry spells, the plant becomes dormant until moisture returns.

The plant is not parasitic, but it can sometimes damage the host tree by over-shading the leaves, thus reducing photosynthesis, or by weighing down and breaking the branches.

Up to 20 feet long.

http://www.sfrc.ufl.edu/4h/Spanish_moss/spanmoss.htm

Host preference?

Spanish moss commonly adopts oak or cypress trees as hosts, but less common on pine, etc.

Chiggers (redbugs) are common residents in Spanish-moss on the ground.

Interactions among epiphytes• Nonvascular epiphytic species (lichens) affect the

quality of host tree for T. usneoides (spanishmoss)

• T. usneoides grew faster on live oak with a dominant lichen than when lichen was hand picked

• Extract of lichen common on poor hosts reduced T. usneoides seedling survival and growth compared to other lichens and rainwater

• Lichens increased T. usneoides seeds and strands that adhered to Ilex opaca (poor host) but not Q. virginiana

Lichens• "Lichens are fungi that have discovered agriculture"--

lichenologist Trevor Goward• Spores• Non-sexual reproductive packages• Breakage when dry to blow, wash away, be carried• Able to shut down metabolically during unfavorable

conditions• Very slow growth, often < 1 mm/yr; some may be

among oldest living things on earth• Environment (fix N), wildlife (tundra), people (dye, etc.)• Indicate good air quality

Lichens• Composite organisms consisting of a

symbiotic association of a fungus with a photosynthetic partner, usually a green alga and/or cyanobacterium. The morphology, physiology and biochemistry of lichens are very different to that of the isolated fungus and alga in culture.

• The algal partners are far less numerous than fungal partners.

• Each lichen species contains a different species of fungi (20% of all) and so it is according to the species of fungi that lichens are classified.

• 13,500 to 17,000 species

Crustose

Squamulose

Foliose and Fruticose

Leprose