Pests Of Irises
Various types of pests may invade your favourite irises, destroying the plants and also ruining the beauty of your garden. Some such insects include aphids, iris borer, iris weevil, scales, thrips, slugs and snails, verbena bud moth, voles, nematodes and others. This article briefly discusses the problems caused by these pests and ways and means to overcome the issue.
Various species of aphids are common all over the garden. They are also found in fields, woods and various other places. In all, there are more than 4,000 species of aphids throughout the world and majority of these pests survive only on some plants that are closely related to one another. Aphids, even the adults, are tiny – not growing beyond roughly 1/8 inch in length. These insects have an elongated pear-shaped form and armed with extended antennae. Frequently known as plant lice, aphids have various different colors – yellow, grey, brown, green, red and black. In fact, aphids may have different colors in different stages of their growth. These pests come with a pair of tubercles (organs akin to tubes), which protrude backward from their abdomen’s top rear. Subject to the species as well as the environment, some aphids have wings, while there are many others which are wingless. When there is a scarcity of food or the conditions are not favourable for aphids, the female insects give birth to additional winged aphids, so that they may fly to other favourable places and set up colonies there.
Aphids survive the winter months in the form of eggs that are protected in plants or other secured places. The unfertilized female aphids that are hatched from the eggs in spring produce live young insects, all of which are females. This is an ideal instance of parthenogenic reproduction or reproduction without fertilization. The mouthparts of aphids are piercing and sucking, which are used by the insects to penetrate the plants and suck their juices. Aphids expel a sweetened substance known as honeydew. This sugary substance draws ants towards it. In reality, honeydew is so dear to the ants that the later may even care for them and tend them like we take care of sheep and other livestock. As the honeydew is responsible for making the plants sticky, it actually helps to sustain a black sooty mold, which is not only nasty, but may even reduce the amount of carbohydrates manufactured by the plants they inhabit, especially when these molds spread over large areas.
When the foliage is extensively damaged by aphids, its appearance may be akin to a pale rash because the aphids have siphoned off the plant juices, counting a portion of the green chloroplasts contained in the green plant cells. Extreme damages by aphids may also result in the leaves becoming curled or bent in an abnormal manner. This is mainly because of the fact that one side of the leaves has been damaged most, thereby losing most of its juices and, therefore, it has become less turgid compared to the other side. Thus, the imbalance in fluid pressure results in the leaves becoming curly.
Initial damage caused by aphids is usually not a major problem for people cultivating iris. However, the threat becomes more as the common aphids also carry iris mosaic virus. Thus, while feeding on the foliage of iris, these aphids usually introduce the virus into the iris plant. This is the main reason why it should be a practice among the iris growers to monitor their garden for presence of aphids.
Compared to other pests, it is easier to control aphids. The simplest means to get the plants rid of these pests is to using a hard fine spray of water on them in the morning. Spraying them in the morning will help to prevent the foliage from becoming wet at night, thereby avoiding fungal diseases. The hard water spray will force the aphids to fall off the plant. While spraying, ensure that the force of water reaches the plant parts underneath and also those that can be seen. It is important to repeat this treatment. On many occasions, using a hard fine spray is the only means to get rid of aphids, especially if you have only a few irises. In case, this treatment fails to get rid of aphids, you may use any insecticidal soap or super fine horticultural oil on these pests. In fact, these are safe substances and nearly as traditional as spraying water using a garden hose. However, you ought to bear in mind that you are spraying each nook and corner of the foliage with a view to remove as many aphids as possible.
Apart from the above mentioned means to get rid of aphids from your favourite irises, you may also use a number of direct biological controls which involve insects that survive on aphids, such as green lacewings, ladybugs and the gall midges. However, prior to using these biological controls, it is essential to go through the instructions carefully or ask your organic-garden supplier for detailed information. In addition to these, other traditional substances used to eliminate aphids include pyrethrins or pyrethrum – the later is a naturally occurring substance in some varieties of plant compost, while the former is an artificially made pyrethrum. Provided the other traditional methods do not yield the desired results, use these as per directions on the product labels. While you need to ensure that your objective is to only use these substances to get rid of the annoying aphids, be sure that you do not spread insecticidal soap, pyrethrins or pyrethrum randomly, as they may also eliminate the insects that are beneficial for the plants.
There is not doubt that the iris borer (scientific name Macronoctua onusta) is the most widespread pest that makes life miserable for irises. Generally, this pest is found in the region extending from eastern Canada and Maine, southwards to the District of Columbia and in the west up to Iowa. Usually, in the south, iris borer is found up to the south of Tennessee. Outside these regions, one will rarely find the iris borer.
Larva of a small moth is among the serious pests that affect the irises most. The body of these larvae has a whitish hue with a shade of light pink to pale red on the rear side, while their head is brownish. The length of the actual moth is under an inch, while its wingspan is anything between 1.6 inches and 2.25 inches. In the region of the thorax, the moth’s body is dark hued, gradually becoming paler brown towards its abdomen. While the two wings on the front have a pale brown background with fine black lines, those in the rear are tan around the external edges, gradually turning to off-white close to the body. In general, the borer moth’s appearance is akin to that of most other moths – plump and hairy. Usually, the wings of this insect are folded towards the back of its body while resting. Both male and female borer moths have the same appearance.
Normally, the borer moth hatches about three to four times in a year, which starts in the beginning of spring just at a time when the foliage of the tall bearded iris is only about 6 inches to 8 inches in height. It seems that the weather has a role to play in these hatches. The borers usually hatch when the spring is warm and if it is cold and damp at that time, they will hatch at a later time.
It is more likely that one will find the indications of the presence of iris borer on iris plants at the start of late spring, generally during May and June. First of all, you need to see if there are any pinholes on the leaves close to their base or in any place where the insects have laid their eggs. Subsequently, try to find young leaves having ragged edges or those that are notched. It has been found that iris borers may start invading the base of the foliage first or on the external leaves of the fans of the foliage. Nevertheless, these insects eventually move toward the fan’s crest as well as towards the middle portion of the tender most as well as freshest leaf. Iris borers often leave a small silver trail which is visible in appropriate light.
Normally, one will find one or additional borers in the iris leaf creases just on the outer surface of the central leaf. While larvae usually survive cannibalistically (eating each other), you may possibly find many of them on a single leaf fan when there is lots of tender foliage. The larva of iris borer travels all the way into the rhizomes, making its way downward via the leaves. In fact, they often eat up numerous rhizomes prior to becoming a pupa.
Afterward in the season, especially during the summer (July and August), it is likely that you will find little stacks insect excrement called frass or “sawdust” in the region of the iris plant’s base. In fact, it is very likely that the borers may have scooped out the entire rhizome by this time of the season.
During the period between the middle and late summer, larva of iris borer grows up to a length of anything between 1 inch (2.5 cm) and 1 1/2 inches (3.75 cm). In case, your iris plant is swarming with these larvae, it is likely that you will find the foliage at the plant’s base looking soggy and slippery. Alternatively, you may also find the plant juices seeping from the borders of the tender leaves. According to iris experts, basically iris borers are omnivorous (voracious eaters of plant as well as animal foods) and besides consuming the iris tissues, the also eat one another. This is the main reason why usually you will find just one iris borer on one rhizome – the others perishing due to their cannibalistic nature.
If you wish to control iris borer in your garden, it is not only important for you to identify these pests, but also have a clear understanding regarding their life cycle. Iris borers usually lay their eggs during the period between mid-September and October end. The adult moths made in the iris leaves as well as the debris on the ground immediately after they hatch out from pupae, which have developed in the ground. The female iris borers lay copious eggs, nearly 200 of them in cluster of 25 to 30 in protected places on the leaves or the old flowering stems. Sometimes, they also lay eggs in the debris on the soil as well as inside the rhizome cracks. The moths are usually feeble flyers and you may detect them hovering around irises on dark overcast days or at dusk. It is important to note that the iris bores are not drawn towards light and, hence, they can be rarely seen even at night when their activity is most, especially during the period between late September and middle of November. If you plant your irises very densely, there is a possibility that there will be more moths as well as more iris borers in the beds.
What is bad news for iris gardeners is that a number of these shiny brownish pupae may possibly sleep through winter and become active when the conditions are favourable. In this instance, the adult iris borers will develop late as well as mate and lay eggs which will hatch much later than the over wintering ones. After the larvae are hatched, they climb over the iris foliage and make small holes in the leaves by chewing them up. After some days, the larvae will again start boring the leaves. In fact, these pests work their way to the leaf sheath base in roughly a week’s time. When the larvae chew the new leaf edges, this causes the leaves to bleed – resulting in the watery, slippery substance at the plant’s base.
As they feed on the iris leaves, the larvae grow bigger and very soon they start eating up bigger parts from the edge of the leaves to their center, making the leaves appear jagged. In due course, these larvae grow bigger feeding on the iris leaves and gradually move towards the plant’s base. Once they reach the base of the plant, the larvae of iris borer make tunnels into the rhizomes while remaining inside the leaf sheaths. These larvae eat up the tissues of the iris rhizome, usually hollowing out the rhizome in such a manner that nothing remains inside it. They reduce the rhizome into a mere shell.
Iris borers also move up to the flowering stalks eating them up as well as the blooms. In fact, the Louisiana irises are more susceptible to invasions by iris borers. Iris borers have a preference for the Louisiana irises. Their second preference is the tall bearded irises, while the Siberian irises come third in the list of their choice. In case iris borers invade Siberian irises they actually result in a disorder and often the entire clump may be lost in the process. In fact, the foliage of Siberian irises is quite sturdy and compared to other iris varieties, it is not all that easy to find iris borers as the tender young central leaves of this plant are more concealed.
In a number of instances, especially when the rhizomes are growing too close to each other, the larvae of iris borer get into one rhizome and subsequently make their way to other nearby rhizomes, eating them up completely. This makes it all the more difficult for the gardener to detect the pests, as they work silently underground. When these larvae turn into adults, they pupate in the ground close to the iris plants on which they have been feeding. Nevertheless, with some practice you can get evidence of whether the rhizomes of your iris plants have been damaged severely by iris borers. Once you are certain about the presence of iris borers, try and locate the larvae and destroy them. If necessary, you may also use a pocket knife to hack into the iris rhizomes. If you find that the larvae have eaten up a major portion of the rhizome, you need to pull out the affected plant and destroy it along with the pests. In any case, such a plant would not have survived the pest attack. One way to prevent the iris plants from be invaded by iris borers is not to plant them too densely. Especially ensure that their rhizomes do not touch each other.
You also need to take proper care of your irises and get rid of all dead foliage at the outset of spring every year. When you do this regularly it will help to get rid of nearly all the eggs of iris borer and also put off the hatching of most eggs in your garden. At the same time, keep a careful eye on your favourite irises during the spring to see if any larvae have been left behind. In case the iris borers have worked their way up into the tender central leaf of the plant, you may run down your fingers through the center of the leaf and pinch out the iris borers. Once you locate the grubs and eliminate them, you will be able to minimize the damage to the plants. In addition, it is suggested that you tear a little portion of the leaf tip which has been affected by iris borer as this will help you to keep an eye on the leaves/ plants where you detected larvae of iris borer.
Another good way to destroy the eggs of iris borer even before they are hatched is to get rid of all old foliage of iris as well as other garbage from your garden prior to the onset of spring. Never use iris foliage to prepare compost, as it may host iris borer as well as other different pests. Apart from ensuring the cleanliness of your garden, you should also inspect all the new plants meticulously. It is advisable that you immerse all the new plants in a very watered down domestic chlorine bleach solution (in proportion of one part bleach to nine parts water). Subsequently, allow the plants to dry out. Soaking the plants in this solution will not only help to eliminate iris borers, but also other pests as well as fungal diseases and various other problems.
Unfortunately, there are some gardeners who do absolutely nothing to control iris borers that invade their irises. Such ignorance can be very risky as iris borers have the potential to obliterate complete iris beds if they are not taken care of. There was a time when many iris growers used strong pesticides with a view to destroy iris borers. However, currently iris growers are much more conservative and they try to avoid using chemicals on their plants, especially those chemicals that may cause unwanted after-effects.
Iris weevil (scientific name Mononychus vulpeculus) may often create problems for people breeding beardless irises. At times, the adult females of this pest are also referred to as iris snout beetle, as their nose appears to be abnormally elongated nose, which not only perforates the ovaries of the flowers of apogon iris, but also lays their eggs inside the ovaries. In fact, they like to lay their eggs in the Iris versicolor (also known as the Blue Flag that is indigenous to the quadrant in north-eastern United States) and Siberian irises. Similar to several other bugs, the iris weevil too has a four-stage life cycle comprising the eggs, larvae, pupae and the adults. However, each year this insect only produces a single generation.
The eggs of iris weevil hatch into a small, plump, legless larva that is somewhat curved. The larvae develop into a pupae inside the seedpods and as the seedpods mature and split open, the adults emerge out of them. On average, the length of an adult beetle is approximately 1/ 5 inch and its rear surface is black, while the body below its wing covers has scales whose hue vary from white to yellowish.
The grown-up iris weevils survive on flower blossoms. As they go deeper into the flower, they make holes and even eat up the seeds as well as other tissues of the seedpod by penetrating its snout or nose into the seedpods. Such invasion of the seedpods by weevils leaves behind rough corky scars on the pods. For reasons unknown, adult weevils usually have a preference for the blue varieties of the tall bearded irises that bloom late in the season. These insects generally stay away from the white Siberian irises. The adult insects survive through the winter months in the debris on the ground close to iris plants.
Eliminating iris weevils is rather easy – all you need to do is to get rid of the seed capsules of the Iris versicolor and Siberian irises and destroy them immediately. People who are engaged in breeding these iris varieties can also avoid damages caused by iris weevils by using cheesecloth or any similar material to bag the seedpods. Used nylon stockings make an excellent material for bagging the seedpods. At the same time, it is also essential to inspect your irises on a regular basis to see if there is any indication of damages caused by these pests.
As far as damages to irises by insects are concerned, scales are rather inconsequential. Various species of scales are found in gardens and a few of them cause serious damages to ornamental as well as other useful plants. Scales are very small insects, almost similar to the aphids. These insects have penetrating and sucking mouthparts to enable them to feed on the sap/ juice of plants. Usually, scale insects invade a plant in great numbers. Such massive infestations may cause the plants to decline or even die.
Scale insects can be classified into two groups – soft scales plus the armoured scales. The female soft scale insects wriggle as undeveloped crawlers and subsequently get used to one spot for feeding. A cotton-like or smooth cover envelopes these insects, leaving their antennae and legs outside the cover. Similar to aphids, the soft scale insects emit honeydew, which usually draw ants and sooty (dirty) mold fungus.
Interestingly, the female armoured scales are deprived of their legs just a couple of days following hatching and then they settle on a permanent feeding spot. Gradually, they develop a solid shell that is by and large detached from the body of the insect. The female insects breed as well as lay eggs beneath this shell. As the shells form a protective covering for the scale insects, they are shielded not only from the environment, but also various sprays used to get rid of different insects from the plants. These insects are only defenceless to spray controls during their crawling stage.
The appearance of the male scales is similar to that of minute wasps and they generally survive for a period that is enough for them to mate. A number species of scale insects reproduce by means of parthenogenesis (an arrangement where the females of a species do not require the males for reproduction). However, when the females reproduce in this fashion, their offsprings are also only females.
Gardeners are lucky that generally there are sufficient ways to control the scale insects from increasing their population abnormally. These means include natural controls as well as predators of these insects, including ladybugs. While the ladybugs are also called ladybird beetles, other predators of scale insects include parasitic wasps. You may purchase these predators from garden centers in large numbers. However, you should refrain from using insecticides to control scale insects, because when you apply insecticides, they will not only kill the scale insects, but also eliminate their predators. Consequently, the population of scale insects will build up abnormally in your garden.
In present times, more and more gardeners are using ultra fine horticultural oils to control scale insects. However, these oils should essentially be used as per the instructions on the product labels. In case of just a couple of iris plants in your garden have been infested by scale insects, it is advisable that you simply destroy the affected plants. On the other hand, if you find that there are just a few scales, you should check the entire foliage carefully and destroy those scales manually. The easiest way is to rub these scales firmly off the plant leaves. Some gardeners, however, find it easier to kill the scales using cotton swab immersed in alcohol.
Bregmatothrips iridis or iris thrips are tiny insects whose life cycle is usually divided into four stages. They invade the irises occasionally, but attack the Japanese irises more often. Generally, the length of iris thrips is below 1/20 inch. Despite their tiny shape, these insects can be recognized easily by the fringe that appears on the borders of their two sets of wings. Although a number of thrips are carnivorous in nature and usually survive on mites and other insects, there are many others that eat plants. These insects use their guttural mouthparts to shred the plant tissues from the surface of the leaves and flowers. Although this makes the plants look unattractive, usually thrips do not kill iris plants. The scars left behind by the thrips have an appearance similar to that of windburn.
Generally, it is rather easy to deal with thrips in your garden. In majority of instances, it is possible to knock down the thrips by using a hard fine water spray, similar to the method applied to get rid of aphids. If the problem is still not solved, you may use other traditional controls for eliminating thrips – especially fine horticultural oil and insecticidal soap. In addition, you can also use biological methods, such as predatory mites, which can be purchased from garden stores. These predatory mites will eat up the thrips inhabiting the irises.
Verbena bud moth
The verbena bud moth (scientific name Endothenia hebesana) is the second most serious iris pest after the iris borer. These pests are a great botheration for iris breeders because they devastate the iris seeds when they are maturing inside the seedpods. Verbena bud moth may be present on iris plants belonging to any species or cultivar and many plants like the verbenas, snapdragons, physostegias, goldenrods and penstemons especially host these pests. These pests can be easily differentiated from the iris weevils as they leave behind a silken coating on the tunnels they make between the seedpods or seed capsules. If you want to be sure if the iris plants in your garden have been affected by verbena bud moth, search for tiny holes or openings in the seedpods. In case these insects are present, it is likely that you will find frass just underneath the hole and a small part of the pupal skin may also be seen sticking out from the hole.
Similar to many other insects, the verbena bud moth also has four stages in its life cycle – eggs, larvae, pupae and adults. The time taken by these insects to pass through the entire cycle is about 45 days. It is really bad news for iris growers that the verbena bud moth has at least four broods every year and these pests also possess the ability to over winter in their larvae or pupae form. This pest lays minute whitish eggs on the seedpod surface and their color changes to somewhat darker just before they are hatched. The tiny larva present on or inside the seedpod has a light-hue, nearly transparent and hairy body with a darker color head. The length of the larva is about 1/2 inch at the time when it pupates inside a glossy brown-hued silk cocoon. Eventually, the adult verbena bud moth crawls out from the seedpod, while the pupal skin protrudes from the hole.
When at rest, the adult verbena bud moth has a triangular shape and its length is just about 1/2 inch. The head of the adult moth is buff-colored, while the eyes are dark. The adult verbena bud moth also comes with small antennae. The abdomen of the verbena bud moth is grey, while the forewings of this pest are grey with metal-like purplish markings. The rear wings of this pest have a pale brownish hue, which becomes darker near the extreme back.
The best way to control the verbena bud moth from increasing its population is to simply get rid of and destroy the seedpods. Since the verbena bud moth has several host plants, it is important to examine the other flowering plants in your garden to see if they too have been affected by this pest. In fact, a method called deadheading flowers just after they fade will help to put off seed production, as well as eliminate places where the pest can breed. In addition, this will also promote reblooming in several garden perennials. Iris breeders who expect to produce seeds will require bagging the preferred seedpods using cheesecloth or nylon from old stockings or anything similar.
Unlike many insects that damage plants, nematodes are microscopic organisms that inhabit the soil. Also called eelworms and roundworms, from the point of view of a gardener, several species of nematodes are found in the gardens – both good as well as bad. Gardeners often use the beneficial or good nematodes to eliminate garden and lawn grubs. On the other hand, bad nematodes invade the plants. They suck off the nutrient-rich plant juices from the relatively small roots of plants. Owing to their minute size, nematodes are generally considered to be a disease, instead of a pest.
If you suspect that a plant has been attacked by nematodes, dig the plant up and examine its roots and see if there are any swollen lumps close to the tips of its roots.
Controlling nematodes is certainly a very difficult task. As we are aware that plants that are intensely in need of water are more prone to be affected by nematodes. Therefore, one way to deal with the problem is to increase the amount of organic substances in sandy soils. This will not only help to prevent water stress, but also augment the soil’s capacity to retain water. In addition, undertaking irrigation on a regular basis will also aid in preventing drought stress. It is advisable that gardeners should take care to circumvent the flood-drought cycles of watering, as this will reduce the risks of damage to your plants by nematodes.
Slugs and snails
Slugs and snails are closely related, as both these pests are basically gastropods belonging to the phylum Mollusca. Slugs as well as snails may consume the foliage of an assortment of plant species, occasionally even those of irises.
Slugs as well as snails lay loads of eggs in soil cracks, debris as well as in moist and shaded places underneath various plants. These pests survive better in damp places and their activity is highest during the night and occasionally also when the days are dark and gloomy. Snails and slugs usually keep off hot and sunny places, in addition to arid conditions. During the daytime when there is sunlight, slugs and snails conceal themselves in protected places, such as below debris or any other dark and damp place. These pests are generally inactive when the temperature drops below 50°F.
One simple means to control slugs and snails is handpick these pests from the iris plants during the night – the time when their activity is highest. It is advisable that you take a flashlight as well as some amount of an extremely diluted alcohol solution (about 3 percent to 5 percent) in a container with a view to anesthetise slugs and snails. Venture out a few hours following sunset when the slugs and snails are most active. Apart from the irises, ensure that you also get rid of these pests from other plants in your garden. In addition to handpicking these pests, you may also take other control means to protect your favourite irises.
Many reptiles and amphibians like to eat these pests. Ensure that you protect the reptiles and amphibians that visit your garden. Setting up barriers with copper foils will help to repel the slugs and snails, as these pests are very sensitive to a number of metal ions. In fact, the copper foil barrier method will be most effective when used in raised iris beds. In addition, strewing boric acid, wood ashes and diatomaceous earth around the iris plants will help to protect them from slugs and snails. These materials are usually washed away by rains and, hence, require to be replaced from time to time.
Using slug and snail traps is yet another excellent means to control these pests in your garden. You may place damp trap-boards made from old wood or grapefruit rinds upside down on the soil in your garden in places showing signs of the existence of these pests, for instance holes found in the foliage. At the same time, ensure that you also examine under these traps daily morning to get rid of or eliminate these pests. Although the conventional beer-baited saucers work well in controlling snails and slugs in your garden, they are not always dependable, especially when they are used alone. One of the major problems in this case is that the pests have a preference for the young and soft foliage close.
While the snail baits are really effective in controlling the pests, at times they may even turn out to be perilous. If you are using such baits you need to be extremely cautious about keeping or placing these baits away from places that are accessible to children as well as pets. If you are not careful, children and pets may be exposed to the toxins used in these baits.
Also known as meadow mice, voles (scientific name Microtus species) may cause severe damage to irises as they often chew the foliage or the roots of the plants. These pests mostly invade the Louisiana irises and Japanese irises. In fact, it appears that voles like to consume anything that is green in color, counting plants as well as rhizomes, bulbs and tubers. Voles are basically rodents that are close relatives of mice. In fact, their appearance too is similar to short-tailed mice.
Voles reproduce actively all through the year and typically each litter comprises anything between three and six progenies. They take about six weeks or a little more to mature. The life span of voles is very short, generally less than a year.
It is interesting to note that often voles move in mole runs, thereby fooling gardeners to believing that moles are responsible for the damage to their plants. In fact, moles are carnivorous animals and only consume earthworms, grubs (larvae) and other smaller animals. They never eat plants, but may cause damage to irises by making tunnels beneath the plants, thereby disturbing their roots. On the other hand, voles also make their individual transport system below the ground as well as on the surface, clearing and mowing the places they run through.
Having a cat as a pet is a very effective way to control voles. Apart from cats, which rejoice on rodents, weasels, owls as well as larger snakes also have a weakness for voles. In addition, using a wire meshing in your garden with spaces of not more than 1/4 inch and up to a depth of about six inches into the soil around the iris beds in the garden is a sure means to control voles. This meshing should be a few inches high on the surface of the soil.
Placing mechanical mousetraps end-to-end beside the runways and in a direction away from your garden may also prove to be effective controls for voles. If these mechanical mousetraps have been positioned appropriately, one doesn’t even require using baits. In addition, you can also effectively keep various animals away from eating anything if you spray heavily diluted hot pepper sauce on the plants. However, the spray is usually washed away by rain and, hence, needs to be replaced.
If you suspect that voles are traveling in mole runs in your garden, you may put off and even eliminate moles as well as voles by placing dry ice inside these tunnels and close all the openings you are able to locate. When kept in the open, dry ice changes back to carbon dioxide (CO2), which puts the moles as well as voles to sleep peacefully, assert some iris experts.
In addition to the above mentioned means, you can also use poison rodent baits to eradicate voles. However, before using them, it is important that you go through the directions on the product labels and use them as per the instructions.
History of irises
The anatomy of irises
Irises in the garden
Propagation of irises
Landscaping with irises
Diseases of irises