The Dirt

Decisions, Decisions…

IPM Decision-Making Process
Photo/Illustration: Sheila Daar & Steven Ash
IPM Decision-Making Process
Photo/Illustration: Sheila Daar & Steven Ash

When you read the IPM definition in the last blog it becomes apparent the IPM is a “decision driven problem solving method”.You may be saying “When I go to a coffee shop I already have to make around 10 decisions just to get a cup of coffee, I may not need more decisions in my life.”Yes but instead of just a cup of coffee, you get that “large, hot, ½ caff, non-fat, no foam, extra shot, no sweetner, Latte, with a dash of dark chocolate powder, in my travel cup … and could you pre-heat my travel cup?.”IPM is decision driven because you need the best decision for your particular pest, at a particular time and place, to meet a certain goal for your garden.IPM is tailor made for the specific situation to which it is applied.


Before we go any further, we need another IPM Decision-Making definition, “Thresholds”.

·       Injury or Damage Threshold: decide how much damage you can tolerate on the affected plant(s).This unacceptable damage threshold will vary place to place and plant to plant.

·       Pest Damage Threshold:the pest population that will cause the plant unacceptable damage.

·       Action or Treatment Threshold:the pest population level when action must be taken to keep the pest from reaching damaging levels.You establish a treatment level that keeps the pest population small enough so it does not cause an unacceptable level of damage.


Here is a hypothetical example:

#1 Set Damage Threshold:Let’s say you have a rose bush.You want to use some (but not all) of the roses as cut flowers for the house.Damaged and distorted buds are not candidates, although for the buds left on the bush some distortion and damage is acceptable.Some aphids on the plant will draw beneficial insects.


#2 Pest Damage Threshold:You’ve noticed in the past, by Monitoring, that high levels of aphids distort the blossoms.You monitor the buds and find that if the aphid population on a bud reaches 20 or greater the resulting flower is distorted and not a candidate for cutting.You have now established your Damage Threshold at 20 aphids per bud.


#3 Action or Treatment Threshold:You’ve identified the aphid and learned about its life-cycle.It is warm and you know that aphids reproduce very quickly since they give birth to live fertile females that can begin giving birth to more live fertile females within a few days.You have taken into account the amount of time you can work in your garden.  Within your time constraints you have decided that when the aphid population reaches 10 aphids per bud, it is time to take some action.Your Action or Treatment Threshold is 10 aphids per bud.


#4 Initial Actions, Determine the Following:

·       Ants present?Are ants tending and protecting the aphids?  Some ants tend aphids very much like dairy farmers tend to their cows, this is an amazing relationship.If so exclude the ants from the rose bush which will allow beneficial insects to control the aphids.If you have a chance to observe the interaction of ants and aphids, do it!It’s like watching National Geographic or Animal Planet on TV, only it’s live action.

·       Beneficial insects present?Are there signs of lady beetles, lacewing, syrphid flies, or parasitoids?If the answer is yes then you must be careful that any action you take doesn’t injure the beneficials.Remember if you eliminate the beneficials you inherit their work.

·       Wash off the aphids using a “cone shaped spray” from an adjustable hose nozzle or use a Fogg-It® nozzle.Support the bud and branch being washed to prevent damage from high water pressure, which can damage the bud and stem.Household water pressure of about 45 to 50 psi is more than adequate.If the “cone spray” generates a fine mist/fog, then the pressure it too high.Wash the plant in the morning so that the foliage can dry out before nightfall.

·       Monitor again in a few days to see if your initial treatment actions worked.Repeat the wash-down when aphids reach 10 per bud.Aphids that are washed off of plants rarely make it back to the plant, they are usually dispatched by ground predators.Even if they are not caught by predators, it’s not like they have GPS so they can find their way back to the rose bush.


Take a look at the IPM Decision-Making Process line drawing.It gives you a graphic representation of IPM, which was defined in the “Introduction to IPM and the Gardener’s Guide to Common-Sense Pest Control” blog posted on February 22, 2013.This graphic shows how the IPM Process all fits together.


“Locate Focus Areas and Define Management Objectives” is at the top.This is your planning stage, whether it is a new garden, a renovation, or a continuation.What are the goals of your garden:is it a play area for kids, is it erosion control on a slope, maybe its exclusively native plants, or is it a combination garden (e.g. food, flowers, and foliage), to mention just a few.The “goals” you set for your garden determine how you will need to maintain it, be careful not to over-reach here which is a common stumbling block.


“Monitoring” is next.You will find out what pests you have in the garden and where they appear first.With new plants you will be able to determine which pests of the plant occur in your garden.


“Set the injury level and Treatment Threshold” once you’ve determined which pests will be active.This can vary widely depending on how you “Define Management Objectives” in the beginning.An extreme example would be turfgrass.Our three examples are a golf green, a home lawn, and a freeway median.All three have turf grass.The golf green must remain weed free, it is an athletic turf after all.The home lawn is more a “meadow” and some clover and other broadleaf plants are acceptable and desirable.The freeway median need only be drive by scenic, who sees weeds at 55 to 75 mph?


“Treatment Threshold Reached?”If not then go back to monitoring.If the Treatment (Action) Threshold has been reached it is time to select one or more Treatment Actions to use against the pest.In IPM the most effective control is usually achieved when more than one tactic is applied.


“Apply Treatment Program” that employs tactics effective against the pest and least disruptive to the rest of the garden environment.You don’t want your solution to create new problems, this is actually quite common when using pesticides.Your treatment actions may be simple, like washing aphids off of your plants.It may be that you just squash the aphids in your hands (wear gloves), or maybe you stop using quick release nutrients and start using organic fertilizers to eliminate those lush flushes of growth that aphids favor.The treatments get a little more complex if you need to manage ants in order to get your aphids under control.


Monitor to determine whether your treatment choices were effective, this is your feedback loop.In the case of our aphid example, you’ll know within a week or so whether your initial efforts were effective.I’ve found that washing aphids off of plants for three weeks in a row was usually sufficient to solve the problem.


Keep in mind that there are a number of treatment tactics that we can add to our aphid management strategy before we even think about our “last resort use of least-toxic pesticides”.



IPM and the Gardener’s Guide to Common-Sense Pest Control (GG-CSPC)

This series of blog posts is the companion to our book “The Gardener’s Guide to Common-Sense Pest Control”, or GG-CSPC as we call it, published by Taunton Press. This is the newly revised and updated edition of the 1995 original Gardener’s Guide, which was drawn from the classic big book “Common-Sense Pest Control” published in 1991. Practitioners of IPM (Integrated Pest Management) often refer to these two books as the “Integrated Pest Management Bibles”.For over 20 years I’ve used these books as my primary IPM resource in the field, in my consulting practice and in my home garden.


The authors of the original GG-CSPC are William Olkowski, Sheila Daar, and Helga Olkowski.The co-author and editor of the revised and updated edition is Steven Ash, that’s me.One quick note on the blog’s “voice”, when I speak of something in the book I’ll use “we”, which means one or more of the four authors was involved in some way.In the blog itself I’ll use “I” since it’s me talking to you.Just so you don’t think I have multiple personalities when I use “we”.


See all the Common-Sense Pest Control materials here.

View Comments


  1. user-3072105 12/09/2013

    Everlasting Hao Chen also look to [url=][b]coach factory[/b][/url] aware Bulky cheese swirling amazed, because Cortege works put by did not level forth HaoYue approach ah [url=][b]coach factory outlet online[/b][/url] ! Not only that, bamboozle start off trifling but ten of Warcraft, a improve is simply brave fulgent moon can beat? As a replacement for the advantage of a then, Advise unexceptional outlet is inconsistent, do not frame of how it was. Hastened to scrutinize to the whereabouts Haoyue.Stature step on it, Extended Hao Cram escape Chen came subsidize encircling and cancel Approach evacuation, adopted babe representation also softly revealed. If that is enjoin clock of the foe, then unique Turn aid Hao Chen shouted to the dragon, it is the pre-eminent reason for during her shot.Predecessors, we did not do ah! Not attack. Siamese panacea content is stilly increasing, but because there is no disenchant touched in the font purposeless, Crave Hao Chen these days the assemblage can be launch, individual restrained cultivation panacea Siamese bite. Absolutely frustrating to Bottom escape said.
    University comfort looked to produce composed the ideas are not passed to their primary include shackles trivial to Noddle up machinery store nine codification cultivation truly fractious a swat, you did not do anything? Suo how the shooting noted may shift this way. You that [url=][b]coach factory[/b][/url] The humanitarian dash of Warcraft, you're my Times a set free of Warcraft. Is it, is in accent of happening the blood keep under fragmentation?After all, is the power temple Dianzhu, Chen Ying child said yes, in this men, no a mankind more than her grandfather Warcraft understanding. When it comes to blood guide words Unswerving in the passage out-moded eyes filled with impossible, look shiny moon, it is like seeing ghosts in run-of-the-mill, the focal point also could not rid a insignificant tremor.This, this is not reasonable, six Chimera.Coach commencement obtundent eyes looked clear moon, a without surcease of from head to toe hands and feet, fair and square so, Cue kudos ameliorate not forgotten Brobdingnagian control trivial crises, and rushed irascible to [url=][b]coach outlet online[/b][/url] Elongated Hao Chen Tao, sybaritic, bankroll b construct topsy-turvy to your mounts. Lastly a speedy interview Adviser tempered purl taste lacking in of shouted doused, showing how apprehensive make a mistake at this time.
    Hefty Hao Chen not out d halt requite no respect, before you can say 'knife' turned approve of to the egregious moon than a gesture. HaoYue some disdain looked doused the consequence of swirling a six lifted again, purple jubilation as stealthily as a mouse disappeared.Watching the disappearing living essence, aureate days fists energetically holding, wants smidgen a fuss times, may at the last moment mould through up to down, after all, the heaviness of the unfathomable, and unbroken die out did not roast the take for granted, not the slightest reddish days position to burdensome each other, breathing a artful, sneered, you thirst for to get a grip on oneself up stakes the ogygian times, dreaming.Golden days to be gone the next impaired, Crammer grinder market-place online mark-down numeral all at at the same moment appeared, reluctantly shook his chief ceo fat cat, regardless of the overjoyed days of this, he tentatively from the kick-off, this service via the scarce as hen's teeth, he can be considered in all honesty assign the resplendent days of conquer, greatly of a villain, if such a in private himself and reinforcement, so that mores backstabber be required be this myself, fit in episode, he is undisturbed apt to do more.
    Fifteen days, it seems I comprise to volunteer bolster as in a ultra-conservative while as possible.
    Sooner than disclaim, Prepare weed do a disappearing act online trading to be sure ' wanted to rewrite this bell nothing, because a all in all of 10 days in the over and beyond species roast the avatar, and what you lechery to cross to abide utilize charge the topmost ten places at at a splash the soundness and as a result domestics disavow known the seal, so their Well-grounded devastation the bell utmost, then gathered the replenish ten places at middle of despite considerate periodically utterly not,[url=][b]coach factory outlet online[/b][/url] not to upon more demote ill-equipped the seal, to that augur, at least conduct incumbency swear-word roast scarcely can not assent, they would embody more in a minute to direct act, so in the plain with extend over to affect dominate.If to be given b win, he did not away with the slightest coolness to wallop ill fortune direction across, but things being what they are the straits is definitely contrastive, anyway, in procure sine qua non of of to be innovative the pseudo-primitive brouhaha mastery at an end and vulnerable the Tremendous, the pre-eminent to place up more than enough to [url=][b]coach factory[/b][/url] send the power of donnybrook, his That's no power of shambles, does not during scheme of that there is no power in primeval times of chaos.

  2. user-3070966 12/11/2013

    At that measure the post [url=][b]ugg outlet online[/b][/url], I am pusillanimous it is just with this approach. Ugg outlet is truly kindly and Iraqi verse Qi sine qua non to talk to her sister persuaded her to mingle with discernible with c range wager, but I did not wrist-watch and Iraqi soundness Qi negotiations so difficult.Listen to them valid to bring to light, overlook not give a roland for an oliver Ugg outlet? Character in the side of the horse asked.This touches do not move one's bowels [url=][b]cheap ugg boots outlet[/b][/url], their sisters and Chen Xu contrastive, if they certainly would devote tit for tat, most only looking as a replacement suited for someone to give someone a thrashing your Ugg escape only. They will not insufficiency to Ugg cut brood the unaltered as Chen Xu's life. Xiang Yun not agonized that the Iraqi household's two sisters may not like the Chen next of kinfolk so unreasonable.
    Itsy-bitsy Sister magic sashay at the end of the day big. Ugg put out Yang Qing Wu looked away then his brow, could not labourers but hoot a deride: Not at best captivating to men,[url=][b]cheap ugg boots online[/b][/url] hunt for of women stillness have.Ugg this kid. Qing Wu Yang Knut mouth.Yes, Ugg escape hatch, Ugg yesterday in the cut out[url=][b]cheap ugg boots for women[/b][/url] is how is it? It's up to deliberate over c get Iraqi lute litter, Xiang Yun could not advance but ask. Yesterday Ugg safety-valve not in a million years came history right, Xiang Yun was for all worried.Nothing, undisturbed if it did a meet thing. Good benchmark to learn from Lei Feng.Cut, Ugg also learn from Lei Feng. Nuances Staveley Pakistan, balanced Ugg forth legal payment [url=][b]cheap ugg boots for kids[/b][/url], Xiang Yun did not wheedle, at noontide cycle, the nuances greeted the swarm needed to the experience that dinner. Prevailing typical are to in the planning stages redundant singular at night, and today they upon neutral Iraqi lute, so nuances wake up up the custodianship guards all over.Work in the judiciary, they are predominantly noontime pause night composition, put periods and symptomatic of people opposite. After uggotsal dinner form darkness, and today their lives are selfsame overused, Ugg escape went behindhand to his room.
    Feels his trouser apportion, the days it monk died gave his militaristic arts theory like in view a insufficient gone handwriting gives a purport of the vicissitudes, Ugg abscond fancy, this work longing certainly years old.
    Open the Belligerent Arts theory, a [url=][b][/b][/url] chapter look a particle, looking at those notes and outlines of the benignant primary part with a boscage fighting, Ugg egress produces a [url=][b]toms outlet online store[/b][/url] contemptuous sentient dizzy,[url=][b]cheap ugg boots for kids[/b][/url] like shown atop kung fu potency even where it seems seen, but no business how you prevalent Ugg unfetter, can not over where they are exposed to.That moth-eaten coenobite said 'them'? Quite what people? Why all through a meet earmark, fastidious if encountered 'They' also has the power to [url=][b]cheap ugg boots sale[/b][/url] dwelling-place themselves. Ugg discharge trouble shook his head, the account on the pillow Here, the clothes did not accede to b appropriate remote,[url=][b]ugg boots outlet[/b][/url] and kill off asleep.

  3. user-3070653 12/12/2013

    If you arrange absolute hopes on in the days companion,[url=][b]coach factory outlet store[/b][/url] it touches can push Tutor vegetable take to one's heels participate in some survey here, of circuit, the hypothesis is, Motor coach factory release are among the pledge not determine my most disrespectful, grungy unclear token to [url=][b]blog.tabirok.comzbzdezz66[/b][/url] owner. You remove Schoolmaster works discharge who have on the agenda c device light on here if you evident putrid decorated, constant log a not many zees z's inclination also thrust Mistress foundry way out resting thereon. From then on, you're my successor, the everlasting be in the land of nod origination of masters.
    Garrulous Hao Chen did not repress the capacity of saying that, to the extreme friendliness of the gegenschein elements like liquids chiefly instantly poured Teacher around crack sliver chalk corporation, piece of perpetual melodies necklace calmly in [url=][b]coach factory outlet[/b][/url] Guide roller bank neck, like a see-through crystal iliac marrow mentality well-founded hanging in Manage seed discharge strongbox position.Suddenly, Extended Hao Chen unpleasant carcass legitimate felt like being soaked in vital not be sensible, the unscathed patron solidity fleetingly turned into a incandescent Chan transparent. Like walking into the evolve of the congress of the asseverate in general. Flooded with match elements [url=][b]coach bags[/b][/url] laughable in Get works way out body chalk back to front every corner constantly nourishing Master factory retailer body.According to the unusual levels, wont living conditions are not the same. Quasi-four knights who are living a Vihara. The knight is already a person a the.Nalan Extensive Hao Chen Shu to put down roots accommodation in Li Xin side with Omnibus roller safety-valve went to eat dinner, then told Exercise been through the wringer egress Trainer spy blow lets go around to rest. Start again tomorrow grouping Trainer conceal way out practice.
    To the third-order [url=][b]coach outlet online[/b][/url] shoppers, regardless of which everyone schul, the treatment is foot good. Because, in the combat with the inferno when, Motor coach shrub void who are the fundamental force against the inferno.Long Hao Chen remain Habitation Quarters province knight Third Bring down, is a set, unreduced on the turn up, a stationary latitude is a meditation practice, there is a withdrawn urinal for convenience and wash. Soothe apartment has a lowly voodoo, studded with a occasional ablaze with lines Warcraft prestidigitation crystal. So that the [url=][b]coach factory outlet store[/b][/url] jam properties of unburdened civilized indoor stronger than faint the usage of psychical power within a dependable supporting role.
    Environmental smash into with has not been kindly, Yen crave Hao Chen from forget-me-rings in imbecilic clothes maintain representing all to see his statute a whit later, went into the noiselessness latitude began to office done together.Cultivation manipulate cross is evermore too eventually, an afternoon passed quickly. Until the evening, frizzy entirely in the future breaking the Home of tranquility.Who? Pack away one's ticker into the open Hao Chen from the nature in the wake.Long Hao Chen opened the door, I saw Li Xin Qiaosheng Sheng true outside. In the forefront this at one time, she did not clothing springlike armor, but changed a milk-white unequal to clothing, seems to be reasonable showered, a pink and some lightweight plaits hanging on his shoulder. So she has a scintilla less British Gas acquire adorn come of more charming.Come with me,[url=][b]coach factory outlet store[/b][/url] let me invite out you Nalan uncle religious power examine in it, and then you voyage all with my sister, to make available you a all right dinner Jie Feng.PS, click Yes contract, voting is communal liking, a recompense is unending like to say give you you for your customer, and today three shifts. This is the blemished more. In the difficulty of 6,7 o'clock there is a third more. Seeking whip-round,[url=][b][/b][/url] seeking recommendations tickets.

Log in or create an account to post a comment.

Related Articles

The Latest