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What is the Orange Dog Caterpillar that Damages Your Lime, Lemon and Orange Trees in Your Backyard?

About the Orange Dog Caterpillar and its effect on citrus trees

Mani Skaria, Ph.D.

Founder & CEO of US Citrus, LLC

Professor Emeritus, Texas A&M University-Kingsville


Orange dog is an enemy of your citrus trees. Some features include:

  1. Looks ugly, has an appearance of bird poop with creamy white markings
  2. Foul odor
  3. Orange dog eats the small leaves of your citrus trees
  4. Its mother is the giant swallowtail butterfly that lays small eggs on citrus leaves. The egg transforms into the next stage called a caterpillar larva with 1½ to 2-inch size with the above three characteristics.
  5. The stinking mechanism is the result of a unique defensive tool of this group of insects. When orange dogs are challenged by an enemy (predators -ants, spiders, mantids). The osmeterium is a gland with an ability to protrude as needed. The gland stores pungent chemicals containing hydrocarbons, terpenes, acids, and ester.

Nature's way of protecting a baby of a butterfly!

Orange Dog Caterpillar

Figure showing an adult butterfly, various camouflage stages of orange dog caterpillar, feeding damage and tongue-like osmeterium. Picture source: University of Florida and UCR. 

How would you kill your enemy, Orange dog? 

They are short-term enemies. Show your biblical tolerance and practice co-existence because, in a short period, they will emerge into a beautiful butterfly. But if the number of enemies is high and the damage exceeds your tolerance level, you may do one of the following:

  1. a) Squeeze each one or
  2. b) Collect and place them in a plastic bag and dispose it of
  3. c) Spray soapy water
  4. d) If you want to be aggressive, apply some bacterial toxin as a biological control agent. Bacillus thuringiensis is a bacterium, its toxin, the BT-toxin is commonly used as a biological control agent. And it is readily available. Interestingly, this bacterium naturally occurs in the gut of caterpillars.

Remember, the orange dog is an irony. One side is an ugly-looking, stinky, poop-like creature with camouflage and chemicals in its pouch. But one day it transforms into one of the natural beauties – an adult, beautiful, butterfly with a great Latin name, Papilio cresphontes, many looks like Oncidium orchids.

Kaffir lime and tree - history, drinks and characteristics

All about the Kaffir Lime

Mani Skaria, Ph.D.

Founder & CEO of US Citrus, LLC

Professor Emeritus, Texas A&M University-Kingsville

Thailand is in the center of Southeast Asia, 68 million people, with Bangkok the capital city. Thai people migrated from Southwest China to Southwest Asia. Thailand is rice producer. Thai food is known for its enthusiastic use of fresh herbs and spices. The flavors in Thai food come from garlic, galangal, coriander/cilantro, lemongrass, shallots, pepper, Kaffir lime leaves, shrimp paste, fish sauce, and chilies. This article is dedicated to Kaffir lime fruit and Kaffir lime leaves.

 Kaffir Lime Thailand

The Nomenclature 

-    The botanical name, Citrus hystrix

-    Known with over 20 different official, Latin synonyms

-    Jeruk purut in Indonesia

-    Jiàn yè chéng in Chinese

-    Kkabuyaw or kulubot in the Philippines

-    Limau purut in Malaysia

-    Trúc or chanh sác in Vietnam.

-    Thai lime in South Africa

-    And in Thailand, it is called Makrud or Makrut (มะกรูด)

And confusingly, the above name is also used in Thailand for the bergamot orange

The tree, fruit, and leaves

-    A tree that may grow to 35 feet tall

-    Leaves are distinctly-shaped in the citrus family -double leaves

-    Green rough fruit, bumpy exterior appearance

-    Fruit ripens to yellow

-    Fruit size, 2-inch wide.

-    The leaves are the most frequently used part of the plant, fresh, dried, or frozen, for dishes such as Tom Yum – a hot and sour Thai soup cooked with shrimp and famous, worldwide (figure below).

Kaffir Lime Curry

-    The peel of the fruit is commonly used in Lao and Tai curry paste; it adds an aromatic, astringent flavor.

-    The zest is used to impart flavor in rums

-    For tastes in rums

-    Crystallized and candied fruit

Medicinal use

-    Traditional medicine in Asian countries

-    Juice as hair shampoo

-    To kill head lice

A Texas distillery called, Treaty Oaks is using Texas-grown Makrut lime (Kaffir lime) zest for the quality gin they produce.


Kaffir Lime Gin

Edible Landscape Citrus Trees

Edible Landscape Citrus Trees

Edible Landscape Citrus Trees

Mani Skaria, Ph.D.

Founder & CEO of US Citrus, LLC
Professor Emeritus, Texas A&M University-Kingsville (

Edible landscaping is the design, practice and the use of food-producing plants in the landscape. Fruit and nut producing trees are ideal for this purpose to bring the aesthetic aspects. Landscape architecture has is becoming a well-received area of specialization. Architects and local landscapers together would bring long-lasting beauty and edible fruit and nuts to your front and yard space. Please note that landscape design is not limited to trees only in addition, there can be berries, vines, vegetables, herbs, and flowers. The plants, designers, and landscapers together bring:

i) Aesthetically pleasing surroundings to your home to enjoy with family and friends

ii) iii) iv)

A fresh food item to the table with control on pesticides used Quality time with family members, bees and birds
Improve the quality of life

fragrance not readily available

Allows you to grow unusual varieties with color, shape, and

1.Landscape citrus trees: Citrus is a family of diverse type of edible trees big size, small, spreading type, or erect. Our US Citrus nursery maintains over 150-different types of citrus. Your designer and your local landscaper would be additional resources for the best selection of citrus varieties that would fit your growing area. The following are some specialties of an ideal landscape citrus tree based on my experience and subject-matter expertise.

2. Citrus tree size and shape. You do not want huge trees in your yard when planted for edible fruit. You should be able to pluck the fruit and to attend to pruning and tender loving care, without the use of a ladder. I am not against a ladder, but I pay more attention to safety aspects.

Ideal height is 5-6 feet tall. You can always maintain the height and shape of the tree with proper pruning. When pruning, practice the art to get enough sunlight into the tree. Always keep sharp pruning shears. It can be used to cut off and physically remove leaves and small branches with pest or disease symptoms. Larger branches would require heavy duty tools.

3. Citrus fruit type. Note that the family of citrus include the types: i) Limes and lemons
ii) Oranges

ix) Citrons
The above would cover the most widely-known types. Remember, there many selections under each type.

Grapefruits and Pommelo

The mandarins (Clementine, Satsuma, Kumquat and kumquat hybrids

Calamondin (Chinese orange) Kaffir lime, Yuzu

Australian finger lime

4. Important considerations to be given.

a) A citrus type that would give fruit year-round (Examples, are limes, lemons, kumquat)

b)  Fruit not readily available in your neighborhood store

c)  Exotic nature (Australian finger lime, new mandarins)

d)  Colors (variegated fruit, pink flowers, variegated leaves)

e)  Unique shape, color, and look (Australian finger lime, Chinotto orange, Bouquet de Fleurs sour)

f) Ceremonial (religious ceremonies, example Citron for the Jewish community, Fingered citron for Chinese, Kumquat for the Chinese New Year, and lime for Indian hand washing after lunch/dinner)

g) Cooking (Kaffir lime, Yuzu)

f) Cocktails (Persian lime, Australian finger lime) Juice (limes, lemon, citron)

5. Immediate gratification and planting size.

The size of the plant at planting usually is a consideration for immediate gratification. Large size citrus plants in 25-gallon containers would bring an instant gratification and aesthetic beauty to the landscape if such plants are readily available. State and federal government agencies regulate citrus tree movement in this country. Therefore, check on the local sources for availability. Whether you are in a citrus producing state or not, always get your tree from a certified, credible source. Many nurseries in non-citrus producing states sell plants that are not required by state and federal inspections and certification. They sell citrus plants that do not meet stringent standards. Citrus is a perennial crop; it is expected to last decades – therefore, it’s worth investing time on researching the right source for your trees.

Large container-grown trees would come with a higher price tag. A 4-5 feet tall citrus tree with flowers or fruit could easily coast from $150 to $350, depending on the variety, size, fruit set, and the type of decorative container. Alternatively, a citrus plant in a 5-gallon container would range from $55 to $95, depending on the variety, size, and fruit set. The price of an economically viable alternative as noted blow would be $30-$45 with micro-budded citrus from US Citrus nursery.

Micro-budded citrus from US Citrus ( is the best alternative one can get in this country to balance cost and time to fruit-set. The early-fruit-bearing attribute of micro- budded plants would be an economically viable alternative to immediate gratifications. A two-year-old, micro-budded lemon at the US Citrus orchard is shown below.

2-Year-Old Persian Lime Tree

6. Container-grown vs. Ground. You can grow citrus in containers – 25-gallon or above. Container trees can be moved around; however, the size and shape to be maintained. The ground is less maintenance. Many newer subdivisions in Texas have caliche-filled ground – it needs to be altered with topsoil and organic materials.

Assorted Citrus Tree Photos

Why the Page Mandarin Makes a Special Patio Tree

The Page Mandarin

Mani Skaria, Ph.D.

Founder and CEO, US Citrus, LLC
Professor Emeritus, Texas A&M University-Kingsville (

Page mandarin would make an extraordinary patio tree because:

  1. It produces fantastic, tasty fruit, easy to peel

  2. Great looking fruit with its deep reddish-orange color

  3. Juicy, rich sweet flavor

  4. Fruit season last long

  5. This fine fruit is not commercially traded; therefore, not available to the general public because of the fruit size and shipping problem

6. The above reasons make Page mandarin a variety that makes an ideal one to plant for home use

In the name: This variety has 75% mandarin and 25% grapefruit in its blood.

A cross between Duncan grapefruit and Dancy mandarin Minneola tangelo, which was released in 1931. A decade later, a cross between Minneola tangelo and Clementine mandarin resulted in a variety released in 196, named Page orange. It is also called Page mandarin.

Technically, it is a tangelo hybrid because of mandarin and grapefruit parents. Tangelos can be a substitute for a mandarin and an orange for consumption purpose. Therefore, the confused nomenclature.

The reasons for commercially not grown goes back to the 1960s when this variety was released in Florida. The state of Florida was emerging as the orange juice capital. The size, shape and the design of juice plants were not in line with using the Page mandarin as an ideal juice source. Unlike today, there was no emphasis on easy-peel varieties. Moreover, plucking the fruit like an orange caused Page mandarin skin peel off easily, causing fruit rot in transit. Commercial planting of this variety at that time required special handling at a time the Florida processing industry was not supportive when juice extractors were designed for round fruit and not flat mandarins.

The tree is best as a patio plant when it is placed to get maximum sunlight. Use a 15-25-gallon size container, with well-draining holes.

A good commercial variety candidate: Today, Page mandarin would be a good candidate for those who are looking for a new fresh fruit for the market. The reasons are:

  1. Unlike in the 1960s, today’s consumers are interested in fresh mandarins, easy to peel, tasty, juicy and colorful. Page has got those characteristics.

  2. Unlike in the 1960s, the importance of the consumer preference is fresh fruit.

  1. The page gives fruit for an extended period of time.

  2. Page has all attributes to demand better returns.

  3. Harvesting, packaging, and shipments are improved to handle cultivars like the Page mandarin.

  4. Fruit harvesting practices, and fruit processing practices are different today compared to the 1960s.

Why Texas Produces the Best Tasting Grapefruit in the World

Texas Rio Red Grapefruit


Mani Skaria, Ph.D.

Founder & CEO of US Citrus, LLC

Professor Emeritus, Texas A&M University-Kingsville

Sorry other citrus-producing states and countries for the above question.

Obviously, we pay the price – our high heat, many 3-digit temperature days.


Texas Grapefruit

A fine and a balanced blend of tartness, sweetness, acidity, juiciness, color, and flavor are very appealing to consumers of grapefruit. The Rio Grande Valley of Texas is known for providing the best tasting grapefruits in the world, including red-flesh grapefruits. Recent examples of Star Ruby and Rio Red grapefruits were developed by Dr. Richard A. Henz of Texas A&M University-Kingsville Citrus Center in Weslaco, Texas, which has become the backbone of the grapefruit industries in many places like south Texas, South Africa, and Israel. Prior to the Rio Red and Star Ruby grapefruits, Texas produced another red flesh grapefruit called the Ruby Red.

Weslaco, Texas is located at latitude 26 degrees north of the equator and 97 degrees west, so it is only 1,800 miles north of the equator. Citrus is a subtropical climate group, with grapefruit as a heat-loving member of the family. In general, citrus trees show little growth below 13oC (=55oF).


Annual Heat Unit

Annual heat unit is a measure of heat plants need and for proper growth and fruit development. This measure is used well in vegetables, and fruit trees. Crops have upper and lower temperature thresholds, outside of which the physiological functions are not normal.


Grapefruit Temperatures

The ideal temperature for grapefruit is above 60 degrees Fahrenheit. South Texas temperature can reach three-digit numbers some days. Grapefruit trees along the coastal areas maintain a warm and stable temperature. In cooler areas, full sunlight and a south-facing planting help grapefruit tree stay warm.


Best Grapefruit in Texas

Grapefruit produces lots of fruit inside. The large size of a grapefruit tree brings a shading effect to the inside fruit. Together, with internal fruit and warm conditions, a grapefruit tree can produce higher quality fruit in places such as south Texas.


Heat Units and Citrus

Heat units are calculated as a function of:

1)    the number of days in a 30-day month

2)    taking 13oC (=55oF) as the temperature minimum for citrus physiology

3)    average monthly temperature of the region 

4)    and the deviation from the minimum times 30 (days) give the heat units.


Following are some of the calculated heat units in various places in tropical and subtropical conditions.


Location                         Region                   Heat Units (Calculated)


South Texas                    Subtropical                     3,900

Orlando, Florida             Subtropical                     3,465

Riverside, CA                 Mediterranean                 1,700

Valencia, Spain               Mediterranean                 1,626

Wakayama, Japan            Maritime, cool                1,951

Palmira, Columbia           Tropical                          3,918


In extreme temperature conditions, shading from other trees or bark whitewash would reduce sunburn impact. In such conditions, the root system is expected to be kept moist always.


Heat Index Chart

Another heat measure is called the heat index (HI) which is an indicator combining the temperature and relative humidity as a measure of perceived temperature on the human body. It is well-explained with the chart taken from the National Weather Service of the United States of America.

 Grapefruit Heat Units - US National Weather Service Chart

Among all the citrus varieties, grapefruit is the only one with an origin in a tropical island – the Caribbean island, Barbados.


Grapefruit from Texas

Want to grow your own Texas grapefruits?

Here at US Citrus, we offer micro-budded Texas Rio Red grapefruit trees.

Perfect for growing your own grapefruit!