Pecan Insect Pest Control and Prevention       Pecan Pests-Birds, Squirrels, and Other Varmits
Pest prevention is by far more cost effective than pest control.  I questioned my knowledge and expertise in this subject prior to offering my advise because we simply have not had a major insect pest problem to deal with in all our years of orchard management.  With that said, let's take a look at insect prevention vs insect control.
With the exception of an occasional outbreak of aphids, we have never had a need to launch an all out war on bugs.  I attribute this to several factors.  First, our orchard is located in West Texas, a dry area, to say the least.  When Georgia's record pecan crop of 2007 flooded the market, they claimed it was due to extremely dry conditions that kept their insect problems to a minimum and allowed for a more marketable crop of pecans.  Even though your pecan trees may be located in a dry geographic area, the methods you choose to irrigate could produce favorable conditions for insect breeding.  I personally am not a fan of sprinkler irrigation.  Besides the fact that this method spreads water to areas of your orchard that simply don't need water, sprinkler irrigation undoubtedly contributes to insect infestation.  I also believe that tilling your orchard provides easy access for those insects such as the pecan weevil that reside through the winter months in your soil.  Practicing good orchard floor management is a key to insect prevention.  Keeping debris, limbs, leaves, and especially those 'early-drop' sticktights picked up eliminates a breeding ground for next year's crop of insect pests.  Removal of dead or broken branches from your trees is just as important.   Last, but not least, be cautious with what you allow to come into your orchard.  Pecans, pecan equipment, or anything else that may have been exposed to a pest infestation at another orchard could import eggs and larvae into yours.  I attribute these practices of pest prevention to our lack of insect pests throughout our orchard. 
It's important to note that most insects that prey on pecan crops are probably in your area.  When aphids magically appear in your orchard after a mid-summer rain, they didn't fly up from East Texas.  They've been over at your neighbor's orchard all summer, you know, the guy that's slinging water all over his ten acres with his sprinkler system.  Pecan weevils are supposedly isolated to specific areas of Texas (see the map below that I uh...borrowed from somewhere.)  However, I suspect that the only main difference between a pecan weevil and the infamous boll weevil that plagues the cotton farmers is what they're laying their eggs in...cotton or pecans. (See more pictures below that I uh...borrowed.)  The point is...those pecan pests are out there.
If and/or when insect prevention fails, insect control must be implemented.  My philosophy is this...use the weakest insecticide needed to get the job done only when it becomes inevitable that your pecan crop is at risk.  We do not just go around spraying insecticide 'just because.'   There are entire seasons that we do not spray at all.  The 'nut  gurus' eagerly provide us with information on what to spray and when, regardless whether any insects are present or not.  Keep in mind that producing a profit is apparently the last thing on their minds.  Insecticides are expensive...and somewhat dangerous.  I believe a healthy pecan orchard can thrive even with the presence of insect predators.   When the need does arrive to utilize an insecticide, choose one that will accomplish your task with the minimal amount of risk and with the least expense.  When those aphids show up in August, I run down to Walmart and pick up whatever they have available that claims to control these bugs.  Last year I spent a total of eighteen dollars and some change on insecticides for our orchard.  I personally never spray any insecticides later than August for safety's sake.  After all, someone will be eating your pecans.

Insecticide Application for Backyard Trees and Small Orchards
Choosing an effective insecticide can be a simple procedure, especially since there isn't many over the counter solutions available to choose from these days.  The insecticides I have found to be effective have become unavailable for most of us.  I found Dursban to be the best all around insecticide, but 'those who know best' have taken it away from the general public, and have since pulled many other effective insecticides off the shelves.  Still there are some pest control products available that will keep insects at bay.  Read the label and see if a particular spray will work on your 'bugs.'  Keep in mind sprays such as Malathon and Liquid Sevin must actually be sprayed 'on the bug' to be effective.  When shopping for an insecticide, look for those claiming to be effective for a longer period of time.  If you wish to 'stay organic,' you can spray your pecan trees with a soap solution or a mixture including jalapeno or habenaro pepper juice.
You will have to have a sprayer capable of reaching the uppermost parts of your tree.  Insecticides can usually be combined with your Zinc applications, cutting down on the time you spend spraying your pecan trees.  Of course you should choose a time when no rain is in the forecast and a calm day to prevent spray from drifting.  Again, don't spray until you see a definate need to do so.  I can tell when it is time to spray for aphids without ever walking out into the orchard.  Those pests attack the grapevine in our backyard long before they pose a threat to our pecan trees, and that 'sticky mess' they create on the windshield of my pickup and patio furniture alert me that it is time to spray.  Thus, when we do apply insecticide to control aphids, we spray all the vegetation on our property.  Otherwise, that grapevine (and Mama's flowers) will cease to exist.

Insecticide Application for Larger Orchards
If you have a large pecan orchard or even a small orchard of large trees, it will probably be necessary to bring out the 'big guns' to control insect infestations.  The same rules regarding insect prevention still apply and will make a noticable impact on your insect problems and your bottom line profits.  However, a backpack sprayer and a bottle of bug spray from Walmart isn't going to get you very far.  Commercial spray equipment will be necessary and commercial pesticides will be needed.  Both require a substantial inventment.  Utilizing commercial agriculture pesticides in Texas will require an Applicator's Licence and a training course on how to use these chemicals properly and safely.  I know there are some of you out there that 'know somebody' who can get you these chemicals.  Be very cautious if you choose to take this route.  I know cotton farmers who would probably 'fix me up' but I am also aware that cotton is not an edibal commodity whereas pecans are.  What may be safe for cotton could be deadly for a food crop such as pecans.  I see cattle and goat herds throughout our area grazing on cotton burs dumped in the pasture and wonder if these toxic pesticides are making their way into our food supply through the meat we purchase at the local supermarket.  I certainly would not want to be responsible for shipping my pecans out across the United States if there was a chance they were toxic.   E-coli outbreaks in spinach and other commodities make national news.  It's just a matter of time before a pesticide poisoning makes the evening news.  Be responsible...and be cautious.
Unless the survival of your pecan orchard is in jeopardy, application of pesticides should be based solely on economic variables.  If you determine that the loss of pecans due to insect damage will be substantial in a financial sense and that the expense of pesticide application is sufficiently justified to offset these losses, then an insect pest control program is an important factor to successful pecan production.   However, to minimize insect infestation which in turn minimizes unecessary operating expenses, proper orchard management including pest prevention must be exercised on a day to day basis.

For information on controlling specific pecan pests, visit our Pecan Library

pecan weevil damage
Pecan orchard pesticide application
Pesticide application drastically effects your bottom line.
pecan weevils in Texas
Pecan Weevils have been found in these Texas areas