Monday, March 27, 2023

Crocus

On a recent trip to Eastern Illinois, we were letterboxing in a historical cemetery and I began noticing dozens upon dozens of crocus in bloom. Recent temperatures had been in the upper 40’s and low 50’s which is ideal for the crocus to peek its beautiful head above ground and bloom in gorgeous colors that range from white to yellow, with purple being the most common variety. These have long been a favorite flower of mine.

Crocuses are part of the Iris family and contain nearly a hundred species Worldwide with many additional hybrid cultivars popular in gardens everywhere. These are low growing plants whose flower stems remain below ground. Depending upon the species they may bloom in autumn or spring, with some spring varieties blooming as early as January. The blooms close up at night as well as on overcast days, preferring sunshine for blooming. Crocus grow from seeds or from daughter cormels found on the corm that will ultimately produce the mature plant. Corms are short, vertical underground stems. These often swollen stems are reservoirs for storing water and nutrients during winter or other adverse weather conditions like drought. After blooming the plant becomes dormant waiting for the right time to bloom again. The autumn blooming crocus, referred to as crocus sativus, are different than our more familiar spring blooming variety. It is ONLY this species of crocus that the spice saffron is derived from.

Image credit: Johan Puisais.
Saffron is a spice produced in the stigma of the flower of this single species of crocus. It has been recorded as far back as c.371-c.287 BC as an important dye for fabric and paintings, as well as for its medicinal qualities and as a spice for a variety of delectable dishes. As a dye saffron differs from pigments in that it will bind to fabrics through a chemical process that pigments lack. The use of a mordant is required to speed up the process and make it lasting. There are garments from ancient times as well as tapestries and paintings all featuring dyes made from saffron that are still vibrant and beautiful today.

Homer paid homage to the crocus in his famous book the Iliad. “Sunrise drew her crocus-like scarf over the sea to bring light to Gods and man alike.” This is likely a description inspired from the vibrant yellowish hue of the bloom from which the name crocus is thought to originate. The Latin word “crocatus” means bright, saffron yellow. The Greek word Krokos also translates to mean yellowish. According to Greek mythology Crocus was a friend to the god Hermes. One day as they played a game of discus Hermes accidentally struck Crocus in the head killing his friend. At the spot where Crocus died a flower of delicate beauty grew. Three drops of Crocus’ blood fell on the flower and these became the stigmata of the flower. Since then, the flower has been called Crocus and the stigmata, saffron.

Crocuses are native to parts of Africa, the Middle east, and Asia. They were first introduced to the Netherlands by the Holy Roman Empire, where now crocus bulbs is the 6th largest in terms of production and exportation. Iran produces 65% of the Worlds saffron, but the highest quality saffron is produced in Krokos, Greece. Saffron is considered the most expensive spice in the World, mostly due to its labor intensive cultivation. The gathering of stigmas from each plant is done by hand, as is all preparation for sale. It is illegal to use modern equipment to harvest saffron. 205 tons of saffron is produced Worldwide annually. It takes 180,000 stigmas from 60,000 flowers to produce 2.2 pounds of saffron which sells for $10,000 US!

In Ancient Egypt saffron was greatly valued not only as a dye, but an ingredient in perfume. Saffron perfume was mixed with tallow or olive oil; at night, saffron threads would be scattered on pillows and sheets for freshness. The crocus flower was not cultivated in ancient Egypt, saffron was consequently imported from Crete, and probably from other empires of the Near East when Egypt was not at war with them. Ironically, as expensive and rare as saffron was, it was abundant in all levels of society; excavations discovered the use of saffron perfume even amongst the laborers who built Merneptah’s tomb. The properties of saffron as a dye were also utilized during embalming rituals. Until the reign of Ramses III and the beginning of the New Kingdom, the final layer of the painstaking mummification process would be a shroud dyed in saffron.

In modern times saffron is known to have many medicinal qualities. The fall blooming varieties are referred to as calchium and contain a chemical called colchicine that is being used in a drug to treat gout. This same variety is also known for its antioxidant benefits and may help fight cell damage and cancer. Other chemicals found in Crocus sativus help fight Parkinson’s disease, Alzheimer’s, depression and treat seizure disorders and even suppress your appetite and help you lose weight. Saffron is also added as a delicious and decadent spice to a wide variety of Asian and Middle Eastern dishes or just to liven up a bowl of rice. While there are many species of crocus, and a wide variety that can be grown in our own yards and gardens, it is only Crocus sativus that contains the properties to treat various medical maladies as well as provide us with saffron. All other crocus varieties should be considered inedible and lacking in the right properties to benefit us medically. 

 

Planting crocus in your yard will not only brighten your landscape, but also provide an early nectar source for hungry bumble bees and other pollinators that have overwintered in a state of dormancy. You may even catch a sleepy bee curled up in the bloom for a restful night’s sleep.  Crocus symbolize happiness, cheer and new beginnings, this coincides perfectly with their appearance in late winter or early spring when we are all anxious for sunshine, warmer days and the greening up of a dreary landscape. Spotting the bright purple or yellow crocus shining brightly on a drab background is sure to bring a smile to your face and faith to your heart that warmer days are on the horizon.

Monday, March 13, 2023

Giant Leopard Moth

One of the most elusive, yet stunning moths found in Missouri is the giant leopard moth (Hypercompe scribonia). These moths are in the the Erebidae family, same family as tiger moths and go by other names such as eyed tiger moth or great leopard moth. Their common name was bestowed upon them in 1790 and comes from the leopard-like pattern on their wings. These are the largest of the tiger moth species found in the Eastern United States. Males are larger than females with a three-inch wingspan and over all body length of around two inches. Both males and females have bright white wings covered in black spots, and blotches. Some spots may be hollow, or open, others are solid. Their abdomen is bright blue with orange spots and males have thin yellow stripes down the side. 

While they are considered common, they are rarely encountered because of their nocturnal habits. Many moths will become active right at dusk, giant leopard moths seem to be more nocturnal than their counterparts and are encountered long after darkness falls. Males are attracted to lights at night and in some areas may congregate in large numbers at porch lights or pole lights. Females on the other hand rarely show up at lights and no one seems to know why. Moths are known to be attracted to light and there is no definitive answer as to why, just a lot of theories. Since moths are unable to answer the why, we are left with conjecture, but the most commonly held belief for this is because it confuses their navigational system.

Moths have evolved to travel by something called transverse orientation. It is similar to humans keeping the North star in our sight to navigate where we are going. Moths keep the moon visible to them in a certain position for the same reason. This helps guide them on their nightly travels in search of food and mates or during migration events. What evolution did not take into account was the endless flood of man-made lights that distract an easily confused animal. It is always best to turn lights off at night if not needed. Not only does this conserve energy, but it helps our night flying insects safely navigate the night, and not be distracted by these artificial moons. 

Moths are often fodder for other animals and find themselves prey to birds, bats, and other small mammals. Mother nature equipped the leopard moth with an ingenious adaptation…ears! Bats use echolocation to capture their insect prey, and many moth species have evolved to avoid this bat equivalent to sonar. Using the ears located near their thorax and upper portion of their wings to “hear” the vibrations and sounds of the echolocation being sent out by the bat they will emit a sound of their own to confuse the bat then drop from the sky avoiding capture at the last minute. Ingenious! 

Females will emit a pheromone (chemical perfume) to attract males, which are capable of smelling her fragrance from about a mile away. Mating may last over twenty-four hours, after which the female will lay her eggs on a wide variety of vegetation including maple, violet, willow, dandelion, and cherry to name but a few. It is highly likely the female perishes shortly after laying her eggs. The eggs will hatch and the young caterpillars will overwinter in leaf litter.

As soon as the temperatures begin to rise in the spring the caterpillars will become active and seek food. These little munchers grow rapidly and complete their life cycle in a matter of weeks. The caterpillars of this species are one of the infamous "wooly bear' caterpillars. They reach lengths up to three inches and are covered in dense black hair with reddish-orange or red colored skin visible between the rows of hairs. They are unmistakable. Many caterpillars with hairy bodies have urticating hairs that can be flicked or released when carelessly handled. These hairs can be irritating to human skin and predators will avoid them for the unpleasantness of the experience. This particular caterpillar is harmless and does not use their hairs in such a menacing way. The hairs are however very dense and stiff and would be uncomfortable for a predator to consume, therefore they are probably not the first choice for those animals who have caterpillars on their menu. 

Adult leopard moths do not feed, as they do not have fully developed mouth parts. Instead, they consume so much food and nutrients as a caterpillar they merely concentrate on mating and egg laying in their adult stage. Many of the plants they consume have toxins in them that would make them unpalatable to would-be predators and they most likely gain some protection from this aspect of their diet. Predators, when faced with a potential meal will think twice if they know it will taste bad or make them sick. 

Giant leopard moths will flash their bright colored abdomen and advertise they taste bad in something called aposematic coloration. Think of the monarchs, with their bright orange wings….predators have learned to avoid that color in nature and consequently the monarch has few worries about being eaten. The same holds true for the giant leopard moth. 

When disturbed these moths have a unique defense mechanism, to deter possible predators they will curl up their abdomen and remain perfectly still or they may drop from the surface they are resting on, in a display of faking their own demise. Throughout nature we see animals using this strategy to avoid being eaten, so it must be beneficial to avoiding predation. Dead things are not as readily eaten as live prey.

If that doesn’t work to distract a predator they have something else up their little moth sleeves. They will release a yellowish liquid from their thorax, near their eyes. This fluid is distasteful to would-be predators and is sure to leave a bad taste in their mouth. It is described as tasting bitter, and I am uncertain who sampled this yellow goo to come to this conclusion. I suppose some individuals will do anything in the name of science, all I can say, is better them than me.

 

Nature is full of surprises and often the most unique and unusual of these come in the smallest packages. Giant leopard moths carry a moniker that brings to mind large predatory cats, but they lack the hunters spirit. They instead do their best to avoid predation by implementing all the little tricks nature equipped them with. Their unassuming lives will occasionally intersect with our own and we should take a minute to appreciate the beauty of Missouri’s majority, the insects!

Friday, March 10, 2023

Alfalfa Weevil

 

https://entomology.k-state.edu/extension/insect-information/crop-pests/alfalfa/alfalfa-weevil.html
An invasive insect is lurking in Alfalfa fields across the Midwest waiting to make itself known each spring. Alfalfa Weevils are believed to originate in Asian countries. They eventually made their way to Europe, where in turn they made their way to the United States in 1904 when they were first discovered in Utah.

Light brown with a dark stripe down their back, measuring approximately ¼ of an inch in length with a pronounced snout these small beetles are rather drab and unassuming. What they lack in the looks and size department, they more than make up for in the appetite department. Adults spend the winter months hidden within the stems of the alfalfa plant, or among leaf litter and other debris. In early spring they become active and egg laying begins. Eggs are laid within the stems of newly developing plants. The larva will make their way to the leaves where they will begin feeding. Newly hatched larvae leave behind tiny pin-hole size feeding evidence that is noticed as the leaves begin to unfurl. As the larva grow, so too does the size of the feeding holes. If the population of larvae is too excessive the leaves will take on a skeletonized appearance and excessively infested fields may look gray or whiteish from a distance. 

https://agcrops.osu.edu/newsletter/corn-newsletter/2018-09/when-begin-alfalfa-weevil-scouting
Another hay crop pest called the Clover Leaf Weevil is very similar in appearance and often shares the same fields with the Alfalfa weevil. To determine which weevil is feeding on your crop, pay close attention to the larvae. The CLW will have a brown head, whereas the AW has a black head. Nearly all the damage done to the annual alfalfa crop is done by the larvae. Adults are not known to cause any significant damage as they typically feed on the edges of the leaves near the bottom of the plants. Although exceptions exist. If the adults begin feeding on the newly developing plant stems after the first cutting, this may cause something known as Bark Feeding and cause damage to newly developing stems.

https://ohioline.osu.edu/factsheet/ENT-32
 With an estimated 15% yield loss on heavily infested fields, typically in central or southern Missouri, some control is needed. Early harvesting can control weevil populations, as too can grazing cattle on infested fields. The estimate is as much as 90% eradication of the weevils in grazed fields. Paying close attention to fields and determining if your field is past a sustainable threshold of weevils is key to controlling them. Pick several stems from various locations within the field, place them in a bucket and shake them. Count larvae and adults. If the number exceeds more than 1 weevil per stem, then chemical intervention may be warranted. It should, however, always be the last resort, not the first option.

 We should always be mindful when making the decision to utilize chemical control of pests. Over usage of chemicals can and will create super pests. The premise is that approximately 5% of pests will survive the chemical onslaught, these nearly 5% will carry a certain amount of resistance into the next generation. Within a few generations most of the pests you are targeting will have some if not complete resistance to the chemicals you are using. Chemicals are not species specific in their target. Meaning, when you spray chemicals you aren’t just killing your desired target, but also beneficial insects, such as lady beetles, lacewings, damsel bugs and other predators of the pest you are trying to eliminate. You are also putting at risk other beneficial insects such as pollinators.

 Numerous predatory wasps have been introduced throughout the United States from Asia and other countries where the Alfalfa weevil originated. These predators evolved with the weevil and provide excellent population control in their native home. Several of these predatory wasps are now well established in the United States and may control as much as 35% of weevil populations in each location. If you have several wasp species within the same field all the better for control. Lady Beetles, Lacewings, and Damsel Bugs are all predatory at some stage in their lives and do an excellent job of controlling pest insects. As too does birds, bats and small mammals. 

https://commons.wikimedia.org/wiki/File:Hypera_postica_P1650452a.jpg

 

During springs when the weather is wet and warm a naturally occurring fungus consumes the weevils, killing as much as 90% of their population. Slow moving weevils that range in color from pale yellow to black are a strong indication this fungus is at play. Within a few days infected weevils will perish.

Being vigilant and keeping a close watch on your fields in early spring will go a long way in making the appropriate decision about control measures of this invasive, and well-established hay pest. Further questions or concerns should always be discussed with your local extension office. They are equipped to offer the best advice for your situation.