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Tuesday, August 26, 2014

Community Garden Thanks First Choice Tree Service!

A hearty thanks goes out to First Choice Tree Service and Ryans Tree Service. They helped out big time with the move of the Provident living community garden to a new location. Those guys successfully moved 24 re-enforced concrete planter beds weighing an estimated 7000 lbs each. Milan Weedman (certified Arborist) with first choice tre service was there to coordinate and supervise with the help of Jason from First Choice and Ryan Brooksby From Ryan's tree service. 

Provident Living Community Garden has a new home and a fabulous community garden! Give those guys some thanks! Pay a visit to Milan at his blog  http://milanweedman.wordpress.com/ 

Red Bird of Paradise

When are figs ready to pick?

Q. We have a small fig tree, about two years old. It has figs in place, but we do not know how to determine when they are ripe for picking.

A. The figs are ready when the neck on the fig starts to bend and the fruit “sags”. Here this white fig is ready and the neck is bent. The green ones are not and are straight.
Once bent you must pick right away. Once they are ready you will pick nearly daily. They do not ripen off of the tree. They must be picked fully ripe.

Understanding and Controlling the Leaffooted Plant Bug

Q. What is the best attack for these pesty, scary looking creatures.  We had them last year.  Haven't seen them yet this season.  Is there something to keep them away? 

A. This first part I am explaining will be a bit late for you now but prevention should start during the winter months when they can be seen in the landscape as overwintering adults ready to lay eggs in the spring. I have seen adults on bottlebrush in home landscapes in southern Nevada and I am sure they are probably overwintering on a number of evergreen plants in winter months. 

Leaffooted plant bug on nopal cacttus.

Leaffooted plant bug on pomegranate.

From: http://www.whatsthatbug.com/2009/02/25/mating-leaf-footed-bugs-3/
Eggs of leaf-footed bug. Photograph by Lacy Hyche, Auburn University.
Nymph of the western leaffooted bug. Photograph by Henry Fadamiro, Auburn University.
Since these insects can fly as adults they will move from plant to plant for sources of food. This means that they will come into your yard from neighbors as well all during the growing season. So just because you control them once during the season you will have them again as long as there is food in your yard for them to eat.

What do we know about leaffooted plant bug?
  • They like to feed on pomegranates, almonds, pistachios, tomatoes, peppers, cucumbers, squash, corn, peach, nectarine and I am sure some others.
  • They are closely related to stinkbugs and squash bugs, feed and reproduce like them and can be confused with them because they look kind of similar.
  • They overwinter from year to year in the landscapes.
  • It takes about 50 or 60 days to produce adults from eggs laid in the spring.
  • They feed with a long hypodermic needle-like mouth that is inserted into soft plant tissue like leaves and fruit.
  • Their feeding early when fruit is developing can cause threads of sap to stick out of the fruit.
  • Their feeding causes misshapen fruit or causes fruits or nuts to drop off of the tree.
  • Their feeding can also cause diseases to enter the fruit.
How to Control Them
They are difficult to control because they hide unless they are swarming and reproducing near the fruit.
Hard or conventional pesticides such as Sevin or synthetic pyrethrins are the most effective for rapid kill. These can be found as ingredients in some common vegetable or fruit sprays in nurseries or garden centers. 

These same ingredients are used commercially where leaffooted plant bug is active. These types of chemicals leave behind a residual on plants that offer some protection for a number of days after they are applied. They also present some safety concerns for homeowners when used without caution in home landscapes so make sure you read the label thoroughly if you choose to go this route.

Organic control is more difficult because these chemicals are short-lived and don’t leave behind much of a residual. You will not control this pest without more work on your part when using organic methods. That is the tradeoff when using organic methods. With conventional pesticides like Sevin a few passes during fruit set and development will give you some good control. Organic methods may require more inspection of the tree and fruit on your part and spraying more frequently. 

Soap sprays like Safers insecticidal soap will give good control if the spray lands on the insects. It leaves no residual once sprayed. Oils like Neem have been reported to give good control. Other oils include horticultural oils and canola oil. Organic sprays like Bt will not work on this insect. Spinosad has not been reported to work on this insect either. Another possibility are pyrethrin sprays which may give you good knockdown when sprayed on them directly.

A common mistake is to think that just because they organic sprays they will not hurt anything except the enemy insect. This is not true. Organic sprays will kill many different insects, good and bad. So directing the sprays at the enemy insects is important. It is also important to spray very early in the morning or near sundown. Spray when there is no wind and cover both the upper and lower sides of the leaves. Do not use one spray over and over. Use several sprays in rotation with each other so you do not end up with an explosion in the population of insects not controlled or building up insect immunity to the spray.

Oleanders Will Grow in Containers

Q. I have two pink dwarf oleanders planted in 18 inch clay pots which have very healthy looking foliage but very few blossoms. One of my "expert" gardener friends says simply that "oleanders don't like pots". Another "expert" says that I'm watering too much. Are either of these guys right or do you have any suggestions that might get some me some blossoms?
Dwarf oleander
A. We have dwarf oleanders at the Research Center in containers and they bloom just fine. Thge dwarf oleander might be a better selection for containers. There might be a couple of things you could try. If the container is small you might have to water more often to compensate for the small soil volume.

Plants in containers need to be repotted every two or three years. Very small containers, every year. Large containers might make it up to five years.
Dwarf oleander pink flowers.
Oleanders that are not getting enough water will look normal but have a very open canopy and not bloom well. Oleanders are high water users and love fertilizer. They do not like to be watered daily but will not do their best if the soil starts drying too much between waterings.

You can try using a soil moisture meter sold for houseplants that you can buy from the nursery for about $7. Water when the dial is about half way between wet and dry, do not let it get totally dry. Next, use a fertilizer like Miracle Gro and water it into the soil about once every six to eight weeks.

Cover the soil in the container with mulch to help keep the soil moist. About three inches would be enough. If oleanders are young, or if they are pruned with a hedge shears, flowers will be delayed or produce very few.

Don't prune with a hedge shears if possible. They should be pruned with pruning shears but not hedged or gimbaled.

Thursday, August 14, 2014

Best Time to Prune Peach is Not During the Summer

Q. We have a peach tree that we harvest in June. When is the best time to prune?

A. Any major pruning should be done after leaf drop in the late fall or during the winter months before leafing out in the spring in February. Some minor pruning, removing some new growth to open up the canopy a bit for better light penetration, can occur during the summer months but this has to be limited to new growth only.

Large Worms Found Munching on Grape Vines

Q. I am finding a large worm varying from 2 – 5 inches in length on my grape vines.  It is roughly 1/2 inch in diameter. The body color varies, green, pink, grey, and brown worms have been removed and destroyed.  Each worm has white diagonal stripes over the length of the segmented body. What is it, and how do I avoid it in the future?

A. You will notice a stiff, semi-curved spine sticking up from its rump as well. This is the hornworm, this spine contributing to its name. The hornworm is commonly found on tomato so it is usually called the tomato hornworm but also damages peppers and eggplants as well.
Not my picture and not from southern Nevada bud demonstrates the "spine"
This is a larva or immature form of the hummingbird or sphinx moth which is a very beautiful large moth. The moth began laying eggs sometime in around March and April so the hornworms have been damaging garden plants since around April or May.
            The hornworm is a voracious eater and can defloiate a plant making it leafless in a very short time. Because of their green color they are hard to see on garden plants even though they are large. On a windless day you can watch your garden for a few minutes and see the plant or leaves move because of their size and weight. This way you can identify their locations.
You can also look for defoliation, entire leaves missing from plants, and that is also a very good sign they are present. Their excrement is large so seeing that is another way to identify their presence. If you have a blacklight that you used for "seeing" bark scorpions at night you can use this at night as well. Hornworms "fluoresce" or shine a different color at night from plants and can usually be easily found this way.
            Control is fairly easy by handpicking when you see them and hunt them down or use the same biological spray that you use for grape leaf skeletonizer or tomato fruitworm; Bt or Spinosad.
            Both Bt and Spinosad can be used by organic gardeners safely. Spinosad is a little rougher on bees than Bt so it is always best to spray any pesticide at dusk or early dawn when bees have not started to forage. Always follow label directions for use.

Peaches Turning Red But the Size of Walnuts

Q. I have a peach tree loaded with peaches about size of walnuts, the branches hanging way down low, they have a red color to them and hard as a rock. What should I do? Is it too early to trim branches? I think cold weather hurt the tree.

A. It is a bit hard to get a handle on the problem without knowing more about which peach tree variety it is and when it normally has its fruit ripen. It is normal for peach fruits to be "hard as rocks" up until a week or so of a normal harvest time.
They may also develop color long before they are ready to harvest. However, judging from the size you mention (walnuts) and color development, it sounds like the fruits were not thinned earlier (removing many small fruits soon after they developed after flowering so that fruit spacing was about 4 inches apart) or the tree was not watered adequately or both.
Not watering with enough water or frequently enough will also result in an open canopy (lots of space between leaves so you can easily see through it) and small fruit.
Unless you are in a very cold climate or you had a very late hard freeze (hard freeze after flowering) I would not guess you had cold damage.

Poor Growth of Lantana Due to Grubs

Q. This season our Lantana has done poorly. For each plant we dig up there appears a bunch of grubs. What's going on?

A. Nice detective work! I would not have guessed this was the problem if you had just sent me a picture of a dying lantana. These guys are decomposers normally and people will find them in their compost piles.
Green june beetle which attacks soft fruit like figs
But these critters will also feed on small, living roots. In large numbers they can cause alot of damage or even death. In small numbers and feeding on roots the plant might appear normal with no apparent damage. The dose makes the poison!
One of the chafers or June bugs they are sometimes called
These are the immature of one of the scarab beetles such as June beetles, metallic June beetles, dung beetles and rose chafers which we have here. Another one that attacks lawn grasses is the "white grub" or sometimes just called "grubs".
One very famous and devastating scarab is the Japanese beetle which we have not yet seen in southern Nevada. 
When you find these immature larva feeding in one localized area around a living plant it is a very good sign they are feeding on it.
They are fairly easy to kill with insecticides such as the conventional insecticide Sevin used as a soil drench or organically using a treatment of bacterial spores. It is marketed under different trade names but if you look in the insect control section of your favorite nursery or garden center you should be able to find it.
Frequently the bacterial spores are referred to as "milky spore" insecticide. There are also nematode good guys that you can apply. I am not sure it is carried in Las Vegas but certainly over the internet.

Grape Not Producing Fruit and Leaves Mottled

Q. My grapes which are about 20 years old and produced grapes last year. I added 4" of mulch dirt and feed with Fruit and Nut fertilizer in spring. There were no grapes this year and the leaves look mottled.

A. From your pictures the leaves look pretty normal with a little bit of wind damage. I suspect that the grapes were either not pruned correctly so that fruit was produced from last years growth (spur or cane pruning) or there might not be enough light.
You will need at least 6 hours of full sun to produce much. Less than this will result in very weak fruit production or no fruit production. If light is a problem it will only get worse as the tree gets larger.
This is plum, not grape, but demonstrates the tearing damage that wind creates particularly on soft new growth.
Lack of light usually results in leaves that are larger than normal and thin, frail leaves easily damaged in wind. If growth from the previous year was totally removed during pruning you will have no fruit production as well.

Privet Dieback Due to Irrigation

Q. We have had these trees in our backyard for 15 years.  All of a sudden, one has a bare spot. What might this be? I enclosed a picture.

Not readers but demonstrates dieback in privet due to infrequent or shallow irrigations
A. From your picture the plant looks like Japanese or Texas privet. Privets are notorious for looking pretty bad, leaf drop and twig dieback when they are not kept moist. They usually do nicely in lawns or when surrounded by other plants with a similar water requirement.
Typically they do not do well in rock mulch and if the soil becomes too dry. So I usually recommend that the rock mulch environment is enhanced with wood mulch or that other plants are included around the base of the plant that require more frequent watering.

Reason Why You Plunge Harvested Fruit into Cold Water

Q. I wrote to you about ripening my plums after I picked them from the tree. I did what you told me to do. Why did you tell me to plunge the fruit into cold water after harvesting?

A. Plums will finish ripening very nicely at room temperature after they are picked. We pick them early, when still hard, and do not let them ripen fully on the tree to avoid most of the damage caused by birds. 
Stark Saturn peach with bird damage
Birds will usually begin “tasting” fruit when they are close to harvest. When we start to see bird damage and the fruit is close to harvest, it is a good indicator that the fruit could be harvested and they will continue to “ripen” off of the tree.
These types of fruit are called “climacteric” since they continue to ripen after harvest. Examples of climacteric fruit are most of the stone fruits like peach, nectarine, plum and plum relatives like pluots. Cherries, even though they are stone fruit, will not continue to ripen after harvest.
The speed at which these fruits ripen depends on the fruit temperature; warmer temperatures cause faster ripening. When you harvest fruit in the heat of the summer, the fruit will have a lot of excessive heat. 
This extra heat is from the environment as well as the fruit's respiration or burning of sugars. We call this heat, “field heat”. It can be very destructive to fruit harvested in the field if it is not removed very soon after harvest or prevented. 
For this reason we try to get the temperature of the fruit lowered as quickly as possible soon after harvesting. You do not want to just put it in the fridge or it will stop ripening.
            One way to do this is just plunge the fruit into icy water to remove the field heat and get it closer to room temperature. After it cools to room temperature, you can let the fruit continue to ripen.

Eggplant Production in the Fall and Winter

Q. Will my eggplant plant continue to produce through the fall and winter?

A. They will produce all the way until later in the fall but produce fruit more slowly. 
Young or immature eggplant in juvenile or growth stage with no flowering. As it reaches maturity it will flower.
Although eggplants will keep growing and flowering, they are more productive if cut back and allowed to regrow during late summer. Cut plants to about 8 to 12 inches in early August, cutting them at a crotch and allowing them to regrow. When you do this it is like giving them a kick in the pants to grow. Their root system is oversized for their top (root to shoot ratio) and they will shift their growth to a more juvenile stage and put on more top growth. When the growth of the top of the plant begins to slow (more favorable root to shoot ratio) then will flower again. Pruning them now removes plant parts that are infested or have alot of damage.

This will mean you need to fertilize after pruning and keep the soil moist to force them to regrow. The second crop will be ready to harvest in about six weeks after cutting back. In some parts of the country eggplants are sometimes trellised and sheared for increased yield and quality later in the season.

The ideal temperatures for eggplant will be 70 to 80F during the day and night time temperatures between 65 to 70F. Very few locations will give those exact types of temperatures. Obviously they will do well in temperatures higher and lower than this. Fruit abortion begins at about 95F with some varieties even though the plant itself can handle heat.

As temperatures get lower than ideal in the fall, eggplant will still set fruit but fruit set is not as reliable and the development of fruit is slower. Eggplant is generally considered more sensitive to cooler temperatures than its cousins, tomatoes and peppers. Flowers will consistently set fruit down to 60 F night time temperatures.
Night time temperatures below 60 F will mean fewer fruit will be set as temperatures get lower. Eggplants begin to get chilling injury at temperatures below 50 F.

Staking may be necessary if plants get big and full of fruit. Fruit touching the ground will tend to spoil. Harvest fruit when they are one third full size. Over mature fruit will be spongy, the seeds begin to harden and the fruit surface becomes dull rather than shiny.

Fruit can be snapped off of the plant but they will keep longer if they are cut at the spiny stem. Leave the "cap" attached. Mulching plants will help to set fruit and improve fruit quality.

Someone Looking for Local Food

Inquiry by a reader to me:

Thank you ! !, .. so much for your valuable information

More folks should know about your resource ! !

I am 71 and a recent widower and living with my daughter
don't have access to do any gardening even so would love to
So Here goes my inquiry :
Are there any local Gardeners
 that have more than enough from there labor ( harvest )
Whether tomatoes  / or any produce / Herbs .. they would share or Sell ?

I live in the NW of LV  Cheyenne & Grand Canyon Rd
My PH. No. is (number withheld by me)

You are Treasure secret to  well kept
A Thankful recipient of your E mail's
(Name withheld by me)

Tuesday, August 12, 2014

Shake Your Tomato Plants!

We hit a spell of cool weather the past few days. Whenever you get this kind of weather during a hot spell, go out and lightly shake your tomato, pepper and eggplants for about 10 seconds each. Tomatoes in particular have trouble setting fruit when temperatures are above 95F.
They set during the cooler weather of spring and then stop setting when it is hot. When we get this cool weather they may go ahead and set if they get visits from bees or if the flowers are disturbed. Shaking the plant releases the pollen that bees normally help release by their invasive visits to the flowers.
Even if you have no bees around, shaking the plants may be enough to help them set fruit while it is cool. They will stop again when it gets hot but you may get a few to set now if they are disturbed.

Water Suspected for Splitting Pomegranates

Q. I wrote to you a few weeks ago regarding splitting pomegranates. Our Homeowners Association switched from grass to desert landscaping. The drip systems were increased to include new plants and older bushes and a new system was added around our older trees. Our water bill for that period was much higher than normal. Is it possible that overwatering in the heat caused the seeds to grow faster, splitting the fruits? I had a good crop last year.
Pomegranate fruit split up the side
A. The splitting of any fruits, whether pomegranate or tomato, is nearly always associated with irrigation or rain. The most commonly held belief is that it is due to irregular irrigation patterns; overly dry periods followed by an irrigation.
It is thought that when the plant has a lack of water the "skin" of the fruit begins to become inflexible and the plant matures the fruit earlier than normal in "hopes" that it can reproduce by hastening seed development and maturity.
Then when an abundance of water is present around the roots, the plant takes up this water and it is transported to the fruit. The fruit, now with an inflexible "skin" can no longer expand like it could when it was immature, and splits.
Another belief is that rainwater is absorbed through the "skin" of some soft fruit, like cherries or tomato, when it is nearly mature and this absorption of water causes the fruit to split.
            Regardless of the reason, fruit splitting is reduced with more regular watering, watering at the appropriate times to prevent the soil from becoming overly dry and the use of surface mulches, particularly wood mulch.

African Sumac With Curled Leaves

Q. New growth on my African sumac has curled leaves and it looks like aphids or something is attacking them. I thought sumacs were desert trees and didn't a have a lot of issues so I'm surprised by this development.

A. African sumac does get aphid problems. Aphids are more of a problem during cool weather and the problem usually disappears with the heat.  But aphids will hang around during the heat and cause problems as well. A good indicator of aphids is the presence of ants.
            If the aphid problem is bad enough you may see leaf yellowing and leaf drop, sticky or glossy leaf surfaces. The stickiness is aphid excrement which is sugary and attracts the ants.
            Soap and water sprays will get them under control if applied every few days. Soapy sprays do not hang around very long.
            Or you can use a systemic insecticide applied to the soil around the base of the tree and watered in. The poison moves up the tree to the leaves and poisons the aphids. This may be safer to use and more environmentally friendly than spraying the entire tree with a pesticide.
            Remember that African sumac is a very messy tree with lots of leaf drop. If you don't want a mess, you might not want African sumac.

Preventing Olive From Dropping Flowers

Q. I have an older olive tree that is very messy. Is there a way to prevent it from blooming in the spring and dropping all its yellow flowers? It also sheds a lot of leaves only during the spring but all year-round. Is there any way to prevent that also?

A. The only consistent way to eliminate or reduce flowering is to spray an olive tree with an appropriate chemical before it blooms. In the past, the most effective timing has been in mid to late February or March using a chemical called Maintain. It needs to be applied by a commercial applicator.
Olive flowers. Some chemicals must be sprayed when the flowers are open to get good fruit drop.
            Commercial applicators have access to other chemicals as well but they usually are not as effective as Maintain. The less effective chemicals are sprayed at the time the olive tree is blooming. These are primarily aimed at fruit elimination, not flower elimination.
            These other chemicals cause the flowers to abort after they are open. It should be obvious if the chemical has to be applied when the flowers are open, it will not do much to eliminate flowers or reduce the release of pollen.
            This is an important question to ask a commercial applicator: when does your chemical need to be applied? If the response is during bloom, then this is not the right chemical to use to eliminate flowers.
            There are two very different products available to homeowners which might be useful to some as a spray. One is fairly effective at eliminating flowers. The other does not do much to the flowers but is fairly good at eliminating fruit.
            When you go to your favorite nursery or garden center, look for sprays that eliminate fruit from trees. Read the label. If the label says it must be sprayed when the flowers are open, it will not be effective as a “flower eliminator”.
            The other spray has a label which tells you to apply it just before the flowers are open. This spray has a much better chance of eliminating the flowers. Again, read the label.
            Regarding leaf drop, olive is evergreen so some shedding is normal since it drops leaves primarily as it puts on new growth. But some leaf drop will occur season-long.
            Excessive leaf drop is not normal. The primary reason for excessive leaf drop throughout the canopy would be lack of enough water. When there is not enough water, then it is normal for a plant to drop leaves to reduce its need for water.
            Make sure your water sources are not plugged, restricted or the clock has not been changed for some reason. Make sure olive trees received enough water during irrigation. You might have to add emitters.

            If the leaf drop is coming from only one or two branches, this is also not normal and could be a sign of disease and you will need to investigate this further.

Pollinator For Pink Lady Apple?

Q. I purchased a Pink Lady apple tree in the fall. It is doing very well. What besides a crabapple tree is a suitable pollinator for this tree? I have been getting many differing opinions on this.
Pink Lady apple harvested in late November. Ooops, the spur broke off. Don't do that!
A. You don’t need a pollinator for that tree. It is self-pollinating in our climate. For the best information on which trees need pollinators you should visit the Dave Wilson nursery website.

No Fruit on Dwarf Orange

Q. I have a dwarf orange tree planted a little over a year ago. There have been no oranges on the tree. I have fertilized and I think I've been watering it correctly. The tree appears to be healthy, just no fruit. Any suggestions?

A. Dwarf orange is not much help to me. The subject of oranges is huge. I need to know what type of orange it is, whether it has produced flowers or not or if the flowers formed but failed to produce fruit. Varieties vary from early ripening - about 8 months from bloom - to late - up to 16 months from bloom.

There are three main groups: The normal fruited, without navels and with light orange colored flesh; the navel oranges, with a distinct navel development at the end; and blood oranges, with red flesh and juice.

There are about 73 varieties but US production focuses on Valencia, Washington Navel, Hamlin, Parson Brown, Pineapple and Temple. 

For home gardening there are many more than these six available from nurseries. Here is a publication from Arizona on citrus varieties.


Best Time for Pruning Oleander

Q. I contacted the Extension Service about my oleander. They sent me a great publication about it but my main concern is pruning. I purchased the dwarf plants two years ago in five gallon containers. They are doing fine but are about four feet high. It is my understanding the plants can be pruned. I need to know the best time to do so and how far down to go without harming them.

A. Pruning oleander is very simple, much simpler than many other plants. You can prune them any time of the year but the best time is in the winter. The incorrect way is to use hedge shears if you want flowers consistently.
Oleander suckering from base after pruning.
You can prune them with hand pruners, preferably a type called a bypass shears. Corona makes good ones that are not very expensive.

Count the number of main stems coming from the base of the plant. Identify the oldest (largest in diameter) stems. Remove one third of these larger stems leaving one or two inches above ground. You are done!
You will do this about every two or three years. No hedge shears. It takes about ten minutes and no mess to clean up! If there are some unusually long ones remove them from the base as well.
Removing larger stems will force new growth like this from the base.

Having said this, the absolute best time to do this is February and March but you can do it any time!

Sap Coming From Peach Trunk to Top of Limbs

Q. Our peach tree has sap coming out from the ground level to the top of one of the limbs. Not sure if too much water, not enough water, too many bugs or what.

A. This is the time of year we start noticing borer damage in peach trees. Sap comes out from the limbs and possibly all along the trunk.
Branch dieback due to peach borer damage.
A clear indicator of borer damage will be that the bark around the sappy areas will peel off, leaving bare wood under it with clear feeding damage (looks like someone took a miniature sander to the wood with no clear pattern) and if you pull enough bark away you will see flattened, oval exit holes from the adult beetles.
Bark peeling away from dying branch due to borers.
You may even see some sawdust under the bark in these "sanded" areas from their feeding. Remove all loose bark all the way into good wood. You may even find a flattened, ugly larva of a borer just under the bark still feeding. Keep it for a pet if you want to.
Borer in removed dead branch
If damage is more than 50% around the limb, cut it off. Do not paint with black tree wound paint. Paint the trunk and remaining limbs with diluted white latex paint (50/50 with water) on the upper surface of all branches down to one inch in diameter and the trunk.

Borers like limbs and trunks exposed to the hot and intense sunlight. White paint keeps limbs and trunks several degrees cooler than brown limbs and trunks and helps to reduce damage to these parts by intense sunlight. 

Ocotillo Two Years and Not Green

Q. I bought an ocotillo 2 years ago and it has yet to turn green and become alive. Should I get a new one? I do not know how to move forward on this.
Not readers ocotillo but still an ocotillo during winter.
A. It may have been dead when you bought it or it may have died after you planted it. Yes, replace it. Two years is long enough to wait. I provided some documents to help get you off to a better start with your ocotillo.

African Sumac Can Be A Messy Tree

Q. I have two African sumac tree and the past few weeks many of the leaves are dropping a lot each day and they are dry or yellow in color.  I am wondering if it is not getting enough water or if with the heat that may be its problem. 
African sumac blooms during the winter and the flowers as well as dropping leaves can be very messy.
A. First of all, African sumac is a messy tree. It can drop a lot of litter on the ground. The female trees can drop a lot of seed. Sparrows and mockingbirds love the fruit and will spread everywhere with sprouts given to neighbors.
            If the tree is in rock landscape and on drip irrigation it might be a lack of water. You do not want to water daily but every 2 to 3 days in this heat at the most. Water with large volumes of water, less often.
            If you do not think you are watering too often then I would run the hose out to it and let it get an extra 20 to 30 gallons under the canopy once a week now if it is an older, established tree.          It is also possible it could be aphids feeding on the leaves. Check them to see if leaves are sticky or shiny with honeydew from aphids. If so, spray with soap and water a few times a few days apart.
            The soil will dry out faster if it is covered in rock mulch rather than wood mulch. Bare soil dries out the fastest. This tree perform better in desert landscapes if it has irrigated plants under its canopy.

Zucchini Not Producing

Q. My friends are giving me grief because I can't grow zucchini or other squashes. I get female flowers with the squash below the flower. I have male flowers, too. We seem to have insects around enough to pollinate other plants. But this fruit withers at about large grape size. What can I do to become one of those zucchini and squash growers who have so much they can't even give it all away?

A. It is possible that they are not open at the same time and having more than one plant should solve that problem. During high temperatures, pollination can be a problem because of sterile pollen.
Zucchini fruits yellowing and falling off
            If the plant has a very tight canopy and bees have a hard time getting to the flowers then this could prevent good fruiting. It is also possible that you have a variety that is not a good performer in our climate.
Male flowers have slender stalk supporting the flower while females stalk, which become fruit,, are much thicker.
            You may have to act like a bee do some hand pollination. You might try hand pollinating. This requires a soft paint brush and transferring the pollen from the male flower to the female flower. This is a pretty good video on hand pollinating zucchini.