Friday, March 25, 2011

Diamondbacks are NOT a girl's best friend




The first Spring after moving into my house I became acquainted, most reluctantly, with one of my 'neighbors' in an early afternoon encounter. I was busily doing laundry upstairs, windows and doors flung open, enjoying the perfect Texas weather. I soon heard both of my dogs barking and didn't think much of it. After a few minutes of this incessant noise-making I stepped outside to quiet them and perhaps catch sight of what they were so focused at. A squirrel, a lizard, a perched buzzard, I thought. As I gave a 'What's going on out there you two? Hush!" they ceased their distressed 'woofs' and I then could clearly make out the unmistakable buzzing sound. I flung myself frantically down the stairs and immediately called the dogs inside with a stern parental voice. Once they were safely inside I walked, in shorts and flip flops no less, casually over to the offended neighbor, "Ok, Mr. Snake, that's much too close. Where are you?" I scrutinized the area where the dogs were a few times. Nothing. I moved a little closer. My eyes scanned the area at least three or four times before I saw him. I then met the gaze of the biggest rattlesnake I have ever seen. My heart jumped. It didn't look real, it was so enormous. I then uttered something that isn't appropriate for all readers. One can imagine.
He was rattling and hissing and coiled and, well, pissed off! He was also much too close to my front porch, to my dogs. I was about to kill a rattlesnake. It wasn't the first one I had killed, there had been two before. But they were smaller. And not quite so evil looking.
Now, anyone that knows me, knows that I am an animal lover and have a very healthy respect for all creatures. Even the ones that scare us and can harm us. I lived several years in Grizzly country for goodness sakes! However, the thought of having this prehistoric looking, venom laden reptile slithering around my house where my dogs nap was not an image I was ok with. If I had seen him on the road, or at the creek, anywhere but 15 feet from my front porch, I would have let him quietly pass. But he wasn't. So...he died. He turned out to be just under 6 feet long. Yikes!
With that said, as a child, visiting Rockmoor I never saw a rattlesnake, or any snake for that matter. I only remember the mason jar full of rattles at the farmhouse that came from the unfortunate victims of Uncle Dee's shotgun no doubt. But when I was younger I didn't know where to look. Now I do. And I see them all the time. Are you getting creeped out yet?
Texas has ten different species of rattlesnakes, more than any other state, except for Arizona. The Western Diamondback rattlesnake is the most common in these parts and chances are if you've seen a rattlesnake at the ranch it was the Western Diamondback. The Crotalus Atrox, as it is scientifically known, falls in the family of 'pit viper'. These are distinguished by their triangular head and small pits under their catlike eye pupils. Pit vipers are usually characteristically thick bodied with short hollow fangs that lie flat in the upper jaw but swing down when the snake opens the mouth to inject venom in prey. The distinctive diamond pattern of the Western Diamondback runs the length of the snakes body serving as a very effective camouflage. Of course, the tell-'tail' (pun intended) is the set of rattles at the base of the snake's spine. These rattles are made up of keratin, the same stuff that makes up fingernails in humans. In prime conditions, snakes shed their skins every 6-12 weeks and each time adding a 'button' to the base of their rattles. This, in turn, replaces the terminal sections that periodically break off. It has been calculated that the rattles cycle between 40-60 times a second when the snake has them in use. This speed produces the high buzzing sound that is so eerily familiar. Once you hear it, you'll never forget it.
At this time of the year, rattlesnakes are most active during the day (April and May) when milder temperatures prevail. However, June through August, rattlesnakes put an end to their diurnal (daytime) activities and seek shelter in the oppressive heat of the day. During these months you are more likely to see a rattlesnake early morning or evening. Just about the time you're taking a walk around the ranch. How convenient.
In Texas, breeding takes place in both Spring and Fall when numbers of diamondbacks are found in close proximity. The female gives birth to about 10-20 young, all born alive. They don't hatch from an egg, which is a commonly held belief. These young snakes leave the mother almost immediately, within hours, and are born with one button at their tail and are fully capable of administering a venomous bite. Many people believe that the bite of a juvenile snake is more venomous because the younger snake does not have as much control over the flow of venom. Makes sense to me, but I can't find the scientific proof to back that up. And I have no intention of testing that theory out. These babies will average 3-4 feet in length when they mature, however there are documented reports of some closer to 8 feet long.
Rattlesnakes aren't aggressive in the sense that they 'will come after you or drop from a tree and attack a person'. In fact, rattlesnakes are poor climbers and one almost never sees them in trees. They favor the rocky slopes and outcroppings. And they won't attack unless they feel threatened or are suddenly surprised. I've gazed for long periods of time up close at a rattlesnake and he didn't seem to mind. But as soon as I got a little too close for comfort he quickly coiled up ready to defend. And be careful around a fully coiled rattlesnake for they are able to strike at a distance equal to half their body length. Of course, common sense goes a long way. NEVER put your hands or feet somewhere that you can't see.
I heard an amusing statistic in my Wilderness First Responder first-aid class once that I always thought was funny. "90% of all snake bites occur in the middle of the day, involving a 20 something male, intoxicated, in the presence of a female." Who knows if that's true, but fellas, don't try and impress the ladies with your snake charmer abilities. Never try and handle a rattlesnake. They may not be aggressive, but they are highly defensive.
And what do you do in the extremely unlikely case that you get bit by a rattlesnake? Go to the hospital fool!! Don't try any fancy tourniquets or incisions to try and suck the poison out, you will likely do far more damage that way. Get medical attention as soon as you can. You need to be administered antivenom. It is highly, highly unlikely that you will die. Most deaths with rattlesnakes involve very small children, very elderly or ill people. And those cases involved individuals who were many hours away from definitive care. (Seton Southwest off 290 is approximately 12 minutes away from the ranch-fyi)
The venom of a rattlesnake contains both neurotoxically active peptide components and a larger complement of enzymatic fractions that destroy blood and tissue. It is a hemotoxin (toxic to the blood) and can work as an anticoagulant. Interestingly, rattlesnakes are not immune to their own venom and can kill another rattlesnake if it is bitten.
Rattlesnakes have few natural predators so they tend to flourish in numbers. Birds of prey, such as hawks or owls, have been known to swoop down on a rattlesnake and make a meal, but it is not a common occurrence. On the other hand, rattlesnakes feed on rodents, frogs, lizards, small birds, and even small rabbits and squirrels. They often don't need to eat but once every two to three weeks and their annual water intake equals roughly their body weight.
There are two snakes in this area that are often mistaken for a rattlesnake, thus, inadvertently, killed because they are thought to be venomous. The Rat snake and the Bull snake are often confused for a rattlesnake due to their similar skin patterns. And to create even more confusion both of these snakes, when stressed, tend to vibrate their tail, giving the impression of their venomous counterpart. Yet, they do not have rattles. Even though both of these snakes has the ability to bite, they are not poisonous. I see Rat snakes fairly often around the ranch. This is a good thing because they help control the rodent population. When I hear the argument that we need rattlesnakes to keep the mice and rats in check, I remind them that there are other, non-poisonous, alternatives. A few years back I started noticing signs of a mouse (or mice) in my house. I often, quite often, keep my door open in nice weather and much to my surprise, or shock I should say, I found a rat snake piled up behind a framed picture in my kitchen. Finding a snake in one's house is never a pleasant experience and not one I care to repeat. However...after the shock wore off and a few days passed I noticed that the mice 'problem' disappeared. I think that 'ol Rat snake sensed food and saw an open door and just made himself at home. (like the mouse, I guess) And then slept off his meal in my kitchen. And much better to have a Rat snake in the house than a rattler. And even better to not have either!!
So not all snakes are 'bad' snakes. In fact, most are good and shouldn't' be killed just because it's a snake. And if you do happen upon a rattlesnake at the ranch, just give it a wide berth and don't make it feel threatened. It doesn't want to be around you anymore than you want to be around it, trust me.
Now that I've completely made everyone paranoid, I promise my next entry will be on something a little more harmless.

Till then,

Sssssssally Anne

Friday, March 11, 2011

Think before you prune!


Well, Spring is getting closer and closer everyday here in the Hill Country. The Redbuds are blooming their beautiful splash of color that is so eye catching in front of a backdrop of green junipers. The fragrant scent of agaritas in bloom wafts in the air as you walk about the ranch. And it's so fun to try and spot the Sandhill Cranes overhead as they fly in V-shaped formations day after day sounding their trumpetlike song heading North to cooler climes. Daytime temperatures reached into the eighties this past week, yet evenings are still cool enough for a jacket. Perfect weather! And if it ever rains again (I feel another brutal summer approaching) we might have some wildflowers to admire.
As the days heat up, not only do the birds and plants become more active, but a particular little beetle comes out of a winter's dormancy. The Nitidulid beetle is rather infamous around here as it is the little critter that carries the deadly spores of the Oak wilt fungus on its body. For those of you not familiar with Oak wilt, it is a deadly disease that has been responsible for the loss of over 10,000 trees in the Austin area over the past 15 years. Oak wilt is found in over 25 states in the U.S. and over 65 counties in Texas alone. Oak wilt is one of the most destructive tree disease in the U.S and is killing oak trees in Central Texas at epidemic proportions. This fungus, known as Ceratocystis Fagacearum, invades and colonizes in the water conducting tissues of healthy oaks. The reaction of the tree to this invasion results in the blockage of these water conducting tissues, ultimately resulting in 'die back.'. Infection and death of a tree can occur very quickly and the disease is able to spread rapidly within an area. Oak wilt has created some very devastating results. In Austin, property values have been considerably reduced in some places due to the loss of old growth Oaks. Also, increased utility bills is something to consider in urban areas when a giant tree has been lost that used to shade the house from the brutal sun.
I understand Oak wilt is probably not what you want to think about when you think of Spring at the ranch. However, I got to wondering that many of you might not be aware of the damage that this fungus is able to produce. And since Rockmoor is home to many beautiful Oaks, I believe a bit of knowledge and education on prevention is beneficial. The more folks visiting Rockmoor that are aware of this disease the better chance we have of preventing it.
There are three types of Oaks, the Reds (Spanish, Blackjack,Shumard, ect.) the Whites(Post, Chinkapin, Lacey, Shin) and the Live Oaks (mainly the Escarpment; what the 'big tree' is down at the creek) Rockmoor has all three types. The Red Oaks are particularly susceptible to oak wilt and when infected generally die within the course of a single summer. The White Oak group is somewhat less susceptible and when infected can live several years after infection, losing branches over time from the top down. The Live Oak susceptibility is somewhat variable, depending on certain conditions, but wilt and death usually occur within 6 months of infection. Oaks with oak wilt stand out with their dead crowns compared to a green canopy in the summer. So much,that infection can be see spotted from the air.
Oak wilt can spread two ways. One is from the transfer of spores from diseased trees to healthy trees by insect 'vectors'(our little beetle friend). The other way is from the movement of the fungus from a diseased tree to a healthy one via root grafts.
The 'overland' transmission begins with a Red Oak. After a tree has died, spores on a fungal mat are formed under the bark. As this mat grows it expands. Eventually this expansion of the mat cracks the bark open. This fungal mat has a distinct odor. The Nitidulid beetle is attracted to this fruity smell. The beetle thus enters the mat to feed. And he gets the sticky spores all over him and then he travels to another tree. These beetles are drawn to the fresh 'wounds' of trees emitting sap. The oak wilt spores then infect another tree. (kinda' sci-fi creepy, huh?) Experiments have shown that these little beetles are able to travel over a mile and can appear on a fresh wound of a tree in 15 minutes. Or less! Because these beetles don't have 'chewing mouth parts' they need some other creature or physical damage to create an open wound. Thus, and this is VERY IMPORTANT, NEVER, NEVER prune an Oak in the Spring to early Summer months (let's say February to June in Texas) unless you plan on immediately painting the wound with a pruning sealant. (black paint works just fine) If a tree becomes damaged from a storm or construction, as will happen, that wound needs to be painted as soon as possible. In extreme cold or extreme heat the beetle is not active, thus these are the best time for pruning Oaks.
Live Oaks tend to be infected by oak wilt via the root system, which is very difficult to control. Trees within 50 feet of one another can be infected. Trees of the same family tend to interconnect their root systems, called root grafts. And the oak wilt will travel through these roots. Spores that have been produced inside the tree travel through the vascular tissue. The leaves on a diseased Live Oak often develop yellow (chlorotic) veins that eventually turn brown (necrotic). This symptom is identified as 'veinal necrosis'. And this a good diagnostic tool to identify oak wilt. The picture at the top of this entry is a classic veinal necrosis image.
Foilar symptoms on Red Oaks is less distinct, they are more readily identified by the fungal mats. These mats on Red Oaks can be found by looking for incongruous narrow cracks in the bark of a dying tree that leads to hollow areas between the bark and wood. It often has the distinct odor of fermenting fruit, that the beetle is so fond of.
So how can you treat Oak Wilt if it's discovered? The most common technique is trenching with a big piece of equipment (trencher, rock saw,ect.) The point of trenching is to sever the root systems from one tree to the next in order to save the healthy ones that have yet to be infected. The area is typically trenched within 100 feet on all sides of the infected area. As far as utilizing a fungicide there is only one that has proven effective for Live Oaks, it's called Propiconazole. Also known as AlamoTM. It is essentially injected into the tree. I've seen both of these methods utilized and it's quite a bit of work. Not to mention very expensive.
Of course the best way to treat oak wilt is prevention. Painting and sealing all cuts on a tree is absolutely essential. This cannot be stressed enough. And if you do suspect an infected tree, quick removal is vital. If everyone keeps an eye out for sick trees and practices common sense when pruning then we should enjoy our healthy Oaks around Rockmoor for generations to come.

Now if we could just find some disease to help us thin out these invasive Ashe Junipers....


Till next time,

Sally Anne


*photo- Oak Wilt Specialist of Texas