Other than the shape of the trunk and the size of the bush, the latex concentration (%DRC) is another factor that has the effect to the production yield of each rubber clone.

Some clones have given high concentrated latex, some have given low concentrated latex.  The clones with high latex concentration will give low production yield and the clones with low latex concentration will give high production yield.  There are a lot of people have misunderstood in this matter.

The high concentration is taken from approx. 35%DRC upward and the low concentration is taken from approx. 37%DRC downward.  The concentration of latex can be easily observed as the tree trunk and bush shape.  The difference is, observing from tree trunk and the bush shape can be seen since the plantation has not yet opened for tapping, but to observe the concentration, it has to observe after the tapping only.

But if we could observe both at the same time, it would be much more benefit.

Naturally, when the rubber trees are still young, it will give low concentrated latex, when it’s become older, the concentration will become higher, the more older the more concentrated, and become too concentrated to flow, it’s called too old to produce any latex.

Owner can notice that, when we have opened the tapping on new plantation, it would take 3-4 days before the essential latex to cease in early years, and after that, it’s able to make rubber sheet.

Essential latex is the latex that the rubber tree has gathered in the collecting vessel during the closing of tapping season, these latex are very concentrated because it has high Microgel, so concentrated  to become lump, unable to use to make rubber sheet, it can only be used to make scraps.

But when it comes to the 3rd – 4th years, 3-4 days open surface interval is not enough, it could take up to 5 days or 1 week because the latex has become more concentrated, it needed more time to open the surface before the essential latex has run out.

The older the longer it takes to open the surface!  But if it were very old, the workers would not stop tapping, they would tap all year round, because for old rubber trees to close the surface as the young tree, it would take longer time to open the surface before obtaining latex to make sheet.

Especially before the cutting down of the trees, they would apply some chemical to accelerate the production, a final root out.

In one year tapping cycle, the weather in the plantation has changed every month.  The changing of weather will effect the rubber’s physiology and the change in the physiology will effect the concentration & production yield.

As in the beginning of open tapping season, rainfall is still less, the soil has not fully hold water, the bark is still hard and able to hold little water, the latex will have high concentration.  When having high concentration, it will stop flowing quickly and will obtain less latex.

Due to the hard bark that has made the cell wall of rubber collecting tube has fewer water, when latex flows. It can absorb less, and therefore, the latex becomes concentrated.

For the rubber clones with high latex concentration will give very low production yield, but for rubber clones with low latex concentration will give higher production yield.

When approaching mid rainy season with more amount of rainwater, the soil started to saturate with water, the bark started to become soft and the concentration of latex will reduce.  When concentration has reduced, it will flow longer and yield more production.

Due to the soft bark, latex collecting vessel’s cell wall will have more water, when latex flows, water can absorb more that has caused the latex to dilute.

In such period, the rubber clones with high concentration will give high production yield, higher than the clones with low concentration.  When the rain started to subside, and the cold wind from Siberia has spread through out, it’s called Wend of rainy season & the beginning of winter season” period.  The coldness will make latex to coagulate slower & cause the latex to flow longer.  The concentration of latex will reduce but will yield more latex.

For the clones with high concentration will give high production yield as well, much higher than the clones with low concentration.

The more concentration will yield more latex.  If the Northern & NE regions have only winter season, and no drought season, growing rubber can be a real wealth.

After the end of rainy season and moving towards the beginning of drought season, the soil started to dry, leaves started to shred, more sunlight has reached the ground, and temperature in the plantation started to rise.  With the influence of cold wind has reduced, the weather in the plantation started to dry up, latex will stop flowing faster, the obtained latex would become more concentrated, but the volume would reduce as well.  Therefore, the production yield would reduce.

At this period, the clones with low concentration will give more production yield and vice versa, and overall production yield will be reduced.

At the beginning of drought period which will be the same period as leaves’ shredding season.  At this period, the amount of rubber leaves will reduced, when leaves has reduced, the latex synthesizing ratio will be reduced and part of rubber particles will reduce more than the fluid part.  Therefore, latex is rather dilute (clear) and has high ratio of protein enzyme.  Therefore, if bringing to make sheet, it will obtain dark colored sheet.

If still continued to tap, even the tree has no leaves left, the tree is still be able to give latex, because the latex synthesizing is not from photo synthesis only.  When it started to blossom young leaves, which will need more nutrition and energy, then it will stop giving latex.

At this period, either it’s the high or low concentration clones; it will give no different in production yield.

Other than the temperature, the tapping system also has the influence to the concentration of latex as well.

Rubber that has stopped tapping for many consecutive days for what ever the reason, such as, continuous rainfall for many days or the festival period, such as, New Year, Christmas, Haralayor etc.

When tapping has restarted, the latex will be very concentrated on the first day, latex’s flow stop quickly and obtain fewer.  The latex will become more dilute on the next days; the flow will stop slower and will yield more latex.

But if tapping consecutively for too long, even though the latex flow will stop slower but it will be much diluted and production yield will be low.  Therefore, for the continuous tapping period, it should not be too short or too long to obtain high production yield.

This is because, during the consecutive days of stop tapping, the condense reaction between carboxylic Group and some protein compound that has Amine group with 2 decimals in the Serum has more time to make the reaction.

When having more time for the reaction, the amount of Microgel obtained is also more, so the molecule has become bigger.

When the molecule becomes bigger, the movement has slow down, the concentration becomes high, when concentration has become high, it will stop flowing faster, the obtained latex become less.

On the contrary, if tapping consecutively for many days, not only the condense reaction period to create Microgel will be shorten, even the time that leaves will synthesize latex is also not enough.  Therefore, latex obtained is diluted, only water and no rubber.

Other than the tapping system., the weather temperature has also influenced the plantation’s production as well.

During the beginning of open tapping season, which is the joint between drought and rainy season, sometimes, the rain has stopped for many days, during this period; the weather is very hot, stuffy, without any wind, so hot that one can smell the soil odor.

The heat that the soil has absorbed during the day will emit out at night, the more heat absorbed the longer it will emit, during the very hot period, even at 23.00 – 24.00 hr. at night, the heat is still emitted.  The workers have to take off their clothes when tapping.

The temperature this high, latex will not flow, the not too concentrated clones will not receive much effect but if it were high concentrated clones, that would be worst.

I have told the workers to tap a few hours earlier, so that the soil would be cooler and able to obtain more latex.  They have worked for a few days and came back to tell me that, it’s not worth, only few additional latex were collected but it would take up to 2 – 3 o’clock in the afternoon to finish the work.  Not enough time left to rest.

Dry weather also has the influence to the plantation’s production, because it caused the latex on tapping panel has high stressing force, so it has coagulated and stop flowing faster.

Dry weather is approx. in Jan. & Feb. the soil is still moist in this period.  The leaves still not shredded and enable to synthesize the latex, but due to, it is changing from cold to drought, so it has strong wind, the air is dry.

With this condition, the high concentrated clones will give low production yield; the low concentrated clones will give high production yield.

The plantation that has overgrown (cluttered) patch, such as, plantation on the mountain will be able to help a lot, because these small crops will emit the moisture, which will reduce the dryness in the air.  Furthermore, these crops will help to block the air stream, so the production yield has not declined so much.

The concentrated or diluted clones or soft bark, hard bark clones, don’t make wrong decision, otherwise, you would not get both latex and wood.